UDK-UDC 05:625; ISSN 0017-2774 • LJUBLJANA, NOVEMBER-DECEMBER, 1995 • LET GRADBENI VESTNIK i Prometnotehniški inštitut Franc ČAČOVIČ Lektor: Alenka RAIČ-BLAŽIČ Tehnični urednik: Danijel TUDJINA Uredniški odbor: Sergej BUBNOV, mag. Gojmir ČERNE, mag. Damijana DIMIC, dr. Ivan JECELJ, Andrej KOMEL, Stane PAVLIN, dr. Franci STEINMAN, Tisk: TISKARNA TONE TOMŠIČ v LJUBLJANI Revijo izdaja Zveza društev gradbe­ nih inženirjev in tehnikov Slovenije, Ljubljana, Karlovška 3, telefon: 061/ 221-587. Žiro račun pri Agenciji za plačilni promet, Enota Ljubljana, šte­ vilka: 50101-678-47602. Tiska Ti­ skarna Tone Tomšič v Ljubljani. Letno izide 12 številk. Letna naroč­ nina za individualne člane društev znaša 2.310 SIT, za študente in upokojence velja polovična cena. Naročnina za gospodarske naroč­ nike znaša 26.250 SIT, za inozem­ ske naročnike 100 US $. V ceni je vključen 5% prometni davek. Revija izhaja ob finančni pomoči Mi­ nistrstva za znanost in tehnologijo, Gradbenega inštituta ZRMK, Zavoda za gradbeništvo ZRMK, Fakultete za gradbeništvo in geodezijo, Univerze v Ljubljani in Fakultete za gradbeni­ štvo, Univerze v Mariboru. Zaslužni profesor dr. Branko ŽNIDERŠIČ, dipl. ing. gradb. - prvi predstojnik PTI 3 0 . o b l e t n i c a u s t a n o v i t v e P r o m e t n o t e h - n i č n e g a i n š t i t u t a s o v p a d a z ž i v l j e n j s k i m j u b i l e j e m n j e g o v e g a p r v e g a p r e d s t o j ­ n i k a , z a s l u ž n e g a p r o f e s o r j a d r . Branka Žnideršiča, k i 2 2 . j a n u a r j a 1 9 9 6 p r a z ­ n u j e 8 5 . r o j s t n i d a n . Č l a n i I n š t i t u t a s m o p o n o s n i n a n j i n m u z i s k r e n i m s p o š t o ­ v a n j e m ž e l i m o o b t e m v i s o k e m j u b i l e j u š e m n o g o z d r a v j a i n z a d o v o l j s t v a i n s e v e s e l i m o n j e g o v i h o b i s k o v n a f a k u l t e t i . PREDSTOJNIKI PTI: Zaslužni profesor dr. Branko ŽNIDER­ ŠIČ, dipl. ing. gradb. - predstojnik PTI od ustanovitve do 1980. Rojen 22. januarja 1911 v Matenji vasi, doktoriral 1944, izvoljen za dekana FAGG 1958,1965 in 1966. Leta 1981 je bil izvoljen za zasluženega profesorja FAGG Univerze v Ljubljani. Predstojnik do leta 1980, ko se je upokojil. Redni profesor dr. Vlasto ZEMLJIČ, dipl. ing. gradb. - predstojnik PTI od 1980 do 1988). Rojen 2. decembra 1919 v Solčavi, doktoriral 1974, izvoljen za dekana FAGG v letu 1979. Predstojnik PTI od leta 1980 do 1988, ko se je upokojil. Izredni profesor dr. Tomaž KASTELIC, dipl. ing. gradb. - predstojnik PTI od 1988 dalje. Rojen 5. aprila 1948 v Celju, doktoriral 1987. Predstojnik PTI od 1988 dalje. GRADBENI VESTNIK GLASILO ZVEZE DRUŠTEV GRADBENIH INŽENIRJEV IN TEHNIKOV SLOVENIJE ŠT. 11-12 • LETNIK 44 • 1995 • ISSN 0017-2774 VSEDIIUA-CONUNTS Poročila - Informacije PTI - FGG SE PREDSTAVLJA ................................................................................ 236 Reports - Information Članki, študije, Tomaž Kastelic: razprave NOVE METODE MERJENJA DOLŽINE IN ZBIRANJA TER PRIKAZOVANJA Articles studies, PODATKOV O CESTAH ........................................................................................... 238 proceedings NEW SOLUTION FOR ROAD DATA CAPTURING AND PRESENTING Alojz Juvane: NASTAJANJE SLOVENSKIH SMERNIC ZA PROJEKTIRANJE CEST................. 243 FORMING A NEW SLOVENIAN ROAD-DESIGNING DIRECTIONS Dušan Fajfar: PROSTORSKI INFORMACIJSKI SISTEM EVROPSKIH AVTOCEST................... 252 EUROPEAN MOTORWAY DATABANK and GIS Marjan Žura, Peter Lipar: PRESOJA VPLIVOV CESTE IN PROMETA NA OKOLJE TER IZBOR OPTIMALNE VARIANTE POTEKA TRASE ................................................................................... 258 THE ROAD AND TRAFFIC ENVIRONMENTAL IMPACT ASSESSMENT AND OPTIMAL ROOM LAYOUT SELECTION Peter Lipar: OPTIČNO VODENJE OSI IN GEOMETRIJSKO OBLIKOVANJE CEST............... 263 OPTICAL LEADING OF AXIS AND GEOMETRICAL FORMING OF ROADS Niko Čertanc^ Bojan Strah: RAČUNALNIŠKO PODPRT INFORMACIJSKI SISTEM ZA ANALIZIRANJE PRO­ METNE VARNOSTI .................................................................................................. 276 COMPUTER INFORMATION SYSTEM FOR TRAFFIC SAFETY ANALYSE Tomaž Maher: PROBLEMATIKA CESTNINE NA SLOVENSKIH AVTOCESTAH - NAJUSTREZ­ NEJŠI NAČIN PLAČEVANJA ................................................................................... 283 TOLL COLLECTING PROBLEMS ON SLOVENE FREEWAYS - THE MOST ADEQUATE TOLLING SYSTEM RTI - FGG se predstavlja Short rew iev of Traffic Technical In s titu te (RTI - FGG) Prva predavanja na gradbenem oddelku nekdanje Tehniške oziroma sedanje Fakultete za gradbeništvo in geodezijo so se po ustanovitvi ljubljanske univerze (poleti 1919) pričela 2.12.1919. Do leta 1951 je bil študij gradbeništva enovit, potem pa se je razcepil v tri smeri: konstrukcijsko, hidrotehnično in prometno. Delo učiteljev je b ilo izrazito usmerjeno v izjemno dobro plačano pedagoško dejavnost. To in skromna potreba po raziskavah in zahtevnih strokovnih delih sta b ili vzrok, da tovrstne dejavnosti na šoli tedaj ni bilo. Učite lji so sodelovali v raziskavah v drugih, posebej organiziranih institucijah, ali pa so to delali kot samostojni avtorji za svoj zasebni račun. Zaradi naraščanja potreb po raziskovalnem in zah­ tevnem strokovnem delu ter vse glasnejših očitkih javnosti o privatiziranju fakultetnih učiteljev je bil leta 1960 ustanovljen Prometnotehniški inštitut FAGG (tedaj je bil v sestavi fakultete še oddelek za arhi­ tekturo), raziskovalna vzporednica pedagoškemu pro­ metnemu odseku s katedrama za ceste in železnice, s svojim internim kontom za raziskovalno in strokov­ no delo. Praktično povsem samostojno razpolaganje s sredstvi iz tovrstne dejavnosti je omogočilo PTI, da se je sprva počasi nato pa vse intenzivneje opremljal z najsodobnejšimi pripomočki in vzporedno z ustrez­ nim stimuliranjem povečeval tudi zanimanje stro­ kovnjakov za delo v njem. Postal je eden izmed najmočnejših inštitutov v državi, pomemben za delo sodišč (raziskave prometnih nesreč) in investitorjev prometnih objektov (prometne študije, ekspertizna dela) ter državne uprave (sestavljanje tehniških pred­ pisov in normativov). Po osamosvojitvi Slovenije se je izjemno povečalo razumevanje in obseg raziskovalnega dela in začel se je intenziven razvoj na področju informatike. Posodobiti je b ilo treba tehniške regulative nove države in izdelati nacionalni program za ceste. PTI je sledil temu in se usmeril skoraj izključno v te dejavnosti. Strokovnega dela, ki je imelo v preteklosti zelo pomemben delež in je zagotavljalo materialno bazo inštituta, sedaj praktično ni več. Ostale so le ekspertize in dajanje strokovnih mnenj za potrje­ vanje najzahtevnejših strokovnih odločitev na pod­ ročju prometa in prometne infrastrukture (ceste, že­ leznice) in ohranilo se je izvedeniško delo za potrebe sodišč. PTI je izjemno pomembno vključen tudi v The Ljubljana University was established in the sum­ mer of 1919. First lectures on the Technical FHigh School, which was soon split to diferent Faculties, began on December 02, 1919. One of these divided Faculties was Faculty of Architecture, C ivil Engineer­ ing and Geodesy (FAGG), today separated to Fac­ ulty of Architecture (FA) and Faculty of C ivil Engi­ neering and Geodesy (FGG). The study of C ivil En­ gineering was uniform till 1951, when it was d i­ vided to the studies of Construction, Hydrotechnic and Traffic. The engagement o f lecturers was exclusi­ vely pedagogical and extremely well paid. Due to several considerations the research and technical works were not present. On the research field the lecturers took an active part in the research works of other, extra organised institutions or executed it for their own account. As the needs o f research and high technical works have grown up and to eliminate negativ public opin­ ion about privatisation of lecturers in year 1960 Traffic Technical Insitute (Prometnotehni'ki in 'titu t - abbr. PTI) was established as a parallel to the peda­ gogical work of the chairs o f roads and of railways. Thanks to its own account (first in the history of Faculty) PTI soon developed its equipment and very good paying conditions increased experts' interest in taking part in Institute's work. Slowly it has grown up as one of the strongest traffic-institutes in the state; an Institut of great significance for the Court of Justice (researches of traffic accidents), for the inves­ tors of great traffic-communication objects (traffic studies, expert works) and for the Slovenian Gover- nement (technical norms and standards, technical advisory works). After Slovenian state-independence the understand­ ing and the extension of research work has extremely increased and an intensive evolution o f informatics has begun. The new state needed the updated tech­ nical norms for the road-designing and National motorway construction program. The main activity of PTI was in this time turned to these fields of work. Universal technical work, essential for the earning the living in the past, was reduced to experts' re­ ports and advisoring for the most important techni­ cal decisions in the field of traffic po licy and traffic infrastructure (roads, railways). The experts' reports for the needs o f Court of Justice were preserved. slovenski "projekt stoletja" - izgradnjo avtocestnega sistema. Pripravil je in vodi strokovna dela za Na­ cionalni program izgradnje avtocest in opravlja sve­ tovalna in najzahtevnejša ekpertizna dela za DARS, d.d.. Strokovnjake PTI je Vlada Republike Slovenije izbrala in povabila k delu v Projektnem svetu DARS, kjer se sprejemajo vse ključne projektne odločitve za slovenske avtoceste. Področje informatike je v zadnjih letih tudi v PTI zadobilo največji zagon. Razvila se je skupina spe­ cialistov, ki samostojno in v povezavi s številnimi inštituti po Evropi in v ZDA razvija in uvaja nove in posodablja obstoječe računalniške sisteme in uspo­ sablja kadre za njihovo uporabo. Poleg študentov, za katere je to usposabljanje del rednega študija, se v posebnih "delavnicah" usposabljajo neposredni uporabniki. To je ena izmed dejavnosti, ki jo kot dodatno pedagoško delo izvaja PTI. Izjemno visoka strokovnost na tem področju je dobila svojo potrdi­ tev v odločitvi IRF (International Road Federation) na zadnjem zasedanju njene generalne skupščine v Glasgovvu, da bo PTI razvijal in postopno oblikoval banko podatkov o evropskem cestnem omrežju. Strokovnjaki-raziskovalci PTI se redno udeležujejo domačih in mednarodnih kongresov in drugih sre­ čanj, kjer strokovni javnosti aktivno predstavljajo svoje dosežke. Odmevnost na te predstavitve je ve­ lika. Najsodobnejši pristop k raziskovalnemu delu in njegova kakovost sta očitno pravilni usmeritvi PTI, ki mu omogočata, da pomembno deluje tudi na svetovnem prizorišču. Nowadays, PTI is deeply engaged in Slovenian so- called "Project of the Century" - Slovenian Motor­ way Construction Project. The main technical works for the "National motorway construction program" were prepared and led by the experts of PTI and some of them were appointed by Slovenian Gover- nement as members o f Project-council of DARS (Mo­ torway company in the Republic of Slovenia, Ltd.) where all the most important environmental and technical decisions are reached. General expert and advising reports of PTI experts support the technical execution of motorway programme. The field of informatics has enormly increased in the last years. In the PTI a special group of experts has been formed to develop and to introduce new computer systems and programs. In few cases in cooperation w ith several institutes in Europe and the US. The education is one part of this job. W hile the education of students in the field of informatics is a normal step in their study, special courses are arranged for the already employed engineers to en­ able them to use informatics programs in their own companies or state governement divisions. Very high professionality of our experts was confirmed by the decision of the last General Assemble of IRF (Inter­ national Road Federation) confiding the develop­ ment and step by step forming of European motor­ ways net data-bank to PTI. The experts o f PTI regularly take part in domestic and international congresses and symposia and pub­ lish the results of their research work. Great re­ sponses confirm the correctness of the decision for the quality and up-to-date researche work in PTI which enable it to be present world-w ide. P redsto jn ik PTI dr. Tomaž Kastelic GIS IN M ULTIM EDIJA NOVE METODE MERJENJA DOLŽINE IN ZBIRANJA TER PRIKAZO VANJA PODATKOV O CESTAH GIS and M ULTIM EDIA new solution for road data capturing and presenting UDK: 656.1.01:681.32 TOMAŽ KASTELIC Zbiranje podatkov je najtežji korak pri implemen­ taciji GIS projekta. Znane metode so za zbiranje podatkov o cestah neprimerne, predvsem zaradi oviranja normalnega prometa in prometne varnosti. Zaradi velikega števila podatkov na razvejenem omrežju so časovno in kadrovsko prezahtevne. Zato smo za zajem vidnih objektov vzdolž cest (signa­ lizacija in oprema cest) uporabili video sistem. Lo­ kacijo določamo s pomočjo merskega kolesa oziro­ ma načrtujemo uporabo GPS. Tako posneta video slika nam rabi za vnos podatkov v bazo; za zajem različnih objektov posnetek enostavno večkrat za­ vrtimo, uporabljamo ga za kontrolo, itd. Z nekaj posebne opreme lahko isti posnetek uporabimo tudi pri predstavitvi v ARC/INFO okolju. Poleg prikaza ceste in opreme na poljubno izbrani podlogi (ske­ nirane karte) nam oznaka na osi ceste kaže mesto, ki ga trenutno prikazuje video posnetek. In narobe: z izbiro lokacije na cesti nam sistem pokaže video posnetek na tem mestu. Uporaba video sistema pomeni velike prihranke v času, ljudeh in seveda denarju, daje pa bolj natančne rezultate kot dosedaj. Data collecting is the hardest step in the GIS project implementation. Known methods are unsuitable for road data capturing because of the traffic safety and they are time consuming for a lot o f different data on the widespread network. So we use video system to take visible objects along the road (road signa- lization and equipment). Location is determined by measurement wheel or w ith the GPS. Video picture is used as the base for data input; we can play it many times for different data input, for control, etc. W ith some special equipment the same video pic­ ture can also be used in presentations in ARC/INFO environment. Beside displaying the road and its equipment on selected background (scanned maps) also the point shows the location on the road while the video picture is moving. Opposite, w ith c lick on the selected location on the road we get from video the situation of this part of the road. Using video system results big savings in time, people and of course money and give much more accurate data as before. AVTOR: Prof. dr. Tomaž Kastelic, dipl. gr. ing. Professor Tomaž Kastelic, Ph. D. 1.UVOD Gospodarjenje s prostorom in objekti v njem zahteva od upravljavca v prvi vrsti natančno poznavanje trenutnega stanja objektov, s katerimi gospodari. To pomeni, da mora obvladovati ogromne količine različnih podatkov, kar je možno le s pomočjo računalniško podprtih informacijskih sistemov. Pri realizaciji informacijskega sistema pomeni največjo oviro zbiranje podatkov. Ko govorimo o prostoru, je to delo še zahtevnejše, saj običajno zahteva ogromno terenskega dela. Le-to je izredno zamudno, kar bistveno vpliva na časovno in cenovno možnost vzpostavitve takega infor­ macijskega sistema. Ker pa se prostor in objekti v njem izredno hitro spreminjajo, postane s tem vprašljiva tudi zmožnost ohraniti ažurnost podatkov v zbrani bazi. Zbira­ nje podatkov o cestah je še dodatno oteženo, ker je potrebno vse meritve in opazovanja izvesti, medtem ko promet nemoteno poteka. Cest zaradi meritev ne moremo enostavno zapreti, delo med prometom pa bi preveč ogrožalo prometno varnost, tako popisovalcev, kot tudi ostalih udeležencev v prometu. Pa tudi če te omejitve ne bi bilo, bi bile vse dosedaj poznane metode zbiranja podatkov prepočasne zaradi ogromne dolžine in razveje­ nosti cest in velikega števila objektov na njih. V članku je predstavljena nova metoda zbiranja podatkov o cestah, ki se nam ponuja z zadnjimi dosežki na področju informatike. Možna rešitev problema zajema podatkov se je pokazala v snemanju situacije na terenu in kasnejši zajem podatkov s posnetka. 2. MERJENJE DOLŽINE CESTIŠČ IN REGISTRACIJA OBJEKTOV Merjenje dolžine cestišč in registracija obcestnih objektov zahteva posebno opremo, ki nam poleg kakovostne slike omogoča tudi natančno določanje lokacije objektov v prostoru. Prvi del opreme sestavlja profesionalna video oprema: kamera, SVHS videorekorder, video monitor in mikrofon. Kamera je fiksno pritrjena v vozilu za vetrobanskim ste­ klom, kjer ima odprt pogled na cesto pred sabo, istočasno pa je zaščitena pred zunanjimi vplivi, predvsem prahom in umazanijo na lečah. Zaradi boljše preglednosti je pri­ poročljivo uporabljati vozilo z višjim sedežem, npr. kombi. Sopotnik poleg spremljanja posnetka na video monitorju prek mikrofona sporoča morebitne opombe o objektih (ma­ terial, težko ločljivi napisi, znaki skriti za zelenjem, vsebina znakov, ki stojijo vzporedno s cesto, itd). Drugi del opreme predstavlja merilnik za merjenje dolžine poti s katerim merimo odmik od začetne točke (sta- cionažo), ki je običajno začetek odseka. Med merilniki, ki smo jih imeli na razpolago (GPS, merilni disk s pritrditvijo na avtomobilsko kolo, CORREVIT L-CE zaznavalo), smo se odločili za najbolj natančno in zanesljivo merilno kolo. Pritrjeno je za vozilom in prek optoelektronskega pretvor­ nika, ki rabi za pretvarjanje mehanske merilne veličine v električno, sporoča spremembo stacionaže posebnemu vmesniku. Ta je povezan s PC računalnikom, kjer se 1. INTRODUCTION An effective management of environment and its objects requests at least that the condition of objects is known as exact as possible. This means that a lot of different data must be maintained, which is possible only with the help of modern computer based information systems. Data collecting is the hardest step in the building of infor­ mation system. When we talk about the space the prob­ lem is even greater because normally a lot of terrain work is needed. The terrain work is very time consuming what essentially impact on time and price component of the implementation of such an information system. The space and objects in it are changing very quickly, so there is not enough only to collect the data but we must keep the data up to date. Collecting data about the roads is even more difficult because all the measurements and observations must be done while the traffic normally runs on. We can not simply close the road while the collecting of data is done. Working in the middle of the traffic is to dangerous for the people making the measurements and also for the other participants in the traffic. Also in the case there is no such limitations all known methods are unsuitable and to slow because of long and widespread road network and a great number of objects on it. In paper is presented new method for road data capturing which is offered by last achievement in the field of infor­ matics. Possible solution of road data capturing is shown in recording the road situation with the video system and later collecting data from the video picture. 2. RECORDINGTHE SITUATION ONTHE ROAD Recording the situation on the road demands special equipment that, besides a good picture, makes possible that the location in the space can be defined to recording. First part of equipment is put together from the special video equipment: camera, VCR, video monitor and micro­ phone. Camera is fixed in the vehicle behind the windshield where the view on the road is clear, and at the same time the camera is protected from the outer influences, espe­ cially dust and dirt on lenses. Because of better lucidity it is recommended to use vehicle with higher seat, the van for instance. Co-driver’s task is, besides watching the re­ cording on video monitor, to inform eventual remarks about the objects (material, hardly separable inscriptions, signs hidden behind the trees, contents of the signs that stand parallel to the road, etc.). Second part of equipment presents measuring wheel that measure distance from the beginning of the road seg­ ment. It is fixed behind the vehicle and give signal to the computer in the vehicle about the change of mileage for every meter through the special interface. Of course, it is necessary to get synchronization between recording and mileage. Special interface was developed for that purpose and communicates with video equipment and measuring wheel. Thus, through the computer it is possible to direct working of the video equipment entirely (beginning, end of recording, pause, returning to selected shranjujejo istodobni podatki o metraži in števca traku na videorekorderju. Seveda je potrebno zagotoviti sinhronizacijo med po­ snetkom in stacionažo. Z ta namen je bil razvit poseben vmesnik, ki komunicira tako z video opremo kot z merskim kolesom. Tako prek računalnika upravljamo celotno delo­ vanje videorekorderja (začetek, konec snemanja, premor, vračanje na izbrano lokacijo, itd.) in krmilimo tudi mersko kolo (postavitev števca na izbrano vrednost in pričetek oddajanja signala). Poseben problem je predstavljalo napajanje vse te opreme v vozilu. Običajni pretvorniki avtomobilske napetosti z 9V v 220V so bili prešibki za napajanje celotne opreme, zato je bilo potrebno tudi ta del opreme ustrezno okrepiti. Kljub profesionalni opremi pa lahko pri meritvah prihaja do manjših odstopanj. Praktično nemogoče je zagotoviti, da bi mersko kolo stalno vozilo po osi ceste (razmišljamo o vakuumski pritrditvi merilnika ob strani vozila). Prav tako vožnja skozi krivine v eni in drugi smeri povzroča določena odstopanja. Zato je umestno razmišljati o nadomestitvi merskega kolesa s satelitsko navigacijo - GPS (Global Position System). Hiter razvoj tehnologije na tem področju nam že omogoča natančnost pozicioniranja okoli 1m (z diferenčno metodo - sinhronizacija fiksnega in gibljivega sprejemnika), pri čemer je možno dobiti podatek vsako sekundo. Natančnost je za naše potrebe povsem zado­ voljiva, medtem ko je nekaj več problemov pri frekvenci meritev. Pri poprečni hitrosti vozila pri snemanju 40km/h pomeni podatek vsako sekundo prevoženih približno 11m. Vsa vmesna stanja je potrebno ustrezno izračunati, med­ tem ko smo pri merskem kolesu imeli pri hitrosti, manjši od 90 km/h, sinhronizacijo s posnetkom na vsak meter (prob­ lem tehnologije video slike - 25 slik/sek). Novi izdelki napovedujejo večje frekvence lociranja (2 meritvi na sekun­ do), s čimer se problem zmanjšuje. Bistvene prednosti GPS so v večji natančnosti na ta način lociranih podatkov in njihovi takojšnji postavitvi v prostor (koordinatni sistem). Pri merskem kolesu moramo lokacijo v prostoru določiti s pomočjo izmerjenih odmikov prek grafičnih podlog (osi cest), implementiranih v GIS okolju. Tu prihaja do odstopanj, tako pri meritvah kot pri zajemu grafičnih podlog. Razvoj sistema je zagotovo v uporabi GPS, vendar trenutno v Sloveniji ta tehnologija še ni uporabljena v večjem obsegu, kar naj bi zagotavljalo nekatere temeljne pogoje za delo (mreža referenčnih postaj, problemi z uporabo GPS v naseljih z visokimi stavbami, hribovita in gorska območja, itd.). 3. VNOS PODATKOV V BAZO Vnos podatkov v bazo na podlagi video posnetkov poteka v posebej za to opremljenem studiu. Osnovo predstavlja video posnetek, ki ga s pomočjo videorekorderja sprem­ ljamo na monitorju (lahko TV). Na računalniku za vnos podatkov teče poseben program, ki komunicira tako z videorekorderjem kot z dodatnim računalnikom, kjer ima­ mo zapisano sinhronizacijo video posnetka in metraže. Podatke vnašamo prek grafičnih podlog na digitalni plošči, ki so za uporabnika mnogo bolj prijazni in zagotavljajo hitrejše in bolj natančno delo. location, etc.), and pilot the measuring wheel (setting the counter to selected value, beginning of signal transmis­ sion). For the needs of synchronization the computer saves the data of counter and distance, for later processing. Special problem was to get enough power for all that equipment in the vehicle. Normal transformer of vehicle tension from 9V to 220V were not strong enough to get enough power, and because of that it was necessary to fix that part of equipment, too. In spite of professional equipment, it is possible to get minor deviations. Practically it is impossible to assure to pilot the measuring wheel through the axis of the road all the time. Driving through the turns in one and the other direction also cause certain deviations. Because of that it is convenient to think about replacement of measuring wheel with satellite navigation - GPS (Global Position Sys­ tem). Very fast development of technology in this area enables accuracy of positioning around 1m (with differen­ tial method - synchronization of fixed and movable re­ ceiver), and with this it is possible to get data every sec­ ond. Accuracy is satisfactory for our needs, but in the meantime one can find more problems with frequency of measurement. When recording with vehicle’s average speed of 40km/h, computer gets data every second or on every 11m. Every intermediate conditions are necessary to compute, meanwhile with measuring wheel we had synchronization with recording for every meter. But new products announce bigger frequencies of localizing (2 measurements per second), and the problem will reduce. GPS essential advantages are in greater accuracy in such a manner localized data, and in their immediate settings in the space (coordinate space). Using the measuring wheel, we have to use mileage data of the object on the digital presentation of the road (axis of road) implemented in GIS to define location in the space. The result of that are deviations, caused both with measurements and captur­ ing the graphic linings. Development of the system is definitely in GPS use, but right now this technology is not used to greater extent in Slovenia. This technology would assure some of the basic conditions for work (net of refer­ ence stations, problems with GPS use in the settlement with high buildings, mountainous and alpine areas, etc.). 3. DATA ENTRY Entering data in the database on the basis of video re­ cordings runs in specially equipped studio. Situation of the road is presented on the monitor (could be TV) with the help of VCR. On the computer for entering data runs special program that communicates with VCR as well as with additional computer. Additional computer stores data of video recording’s synchronization and mileage. Data are entered over graphic input menu on the digitize tablet. Graphic interfaces are more user friendly and they assure faster and more accurate work. With help of revolving button on VCR, we move the picture until we find one of the objects that we want to enter (we can move the picture backward and forward with optional speed independently of the speed of the vehicle while recording). At the chosen object we stop the picture and S pomočjo vrtljivega gumba na viedorekorderju vrtimo posnetek, dokler ne najdemo enega od objektov, ki ga želimo vnesti (posnetek lahko vrtimo naprej in nazaj s poljubno hitrostjo neodvisno od hitrosti vozila pri sne­ manju). Ob izbranem objektu posnetek zaustavimo in objekt poiščemo na grafičnem menuju digitalnika. S pri­ tiskom na gumb na izbranem objektu se nam avtomatično v bazo vpiše koda objekta in stacionaža na odseku. Prek menijev lahko vnesemo še ostale podatke o objektu, za morebitne posebnosti pa lahko uporabimo tudi tipkovnico. Nato lahko nadaljujemo s pregledom posnetka, dokler ne pridemo do konca odseka. Za vnos ostalih objektov pre- vrtimo posnetek na začetek, zamenjamo menu na digitalni plošči in lahko pričnemo z novim vnosom. Tak način dela se je izkazal kot izredno učinkovit. Na terenu potrebujemo minimalno število oseb, ki v kratkem času lahko posnamejo obsežne dele cestnega omrežja. Vnos podatkov v bazo nato poteka doma v mirnem okolju, z možnostjo kontrole vnešenih podatkov, kar zagotavlja bistveno višjo kakovost podatkov. look for the object on the input menu. With the press on the button on the chosen object, code of the object and mileage on the segment are automatically entered in the database. Over the input menu we can enter the other data about the object; for the eventual specialties we can also use keyboard. Then we can continuo with the survey of the recording until we come to an end of the segment. For entering the other data, we can rewind the recording on the beginning of segment, change the input menu on the digitize tablet and we can start with the new enter. Such manner of work showed to be very effective. On the road we need minimal number of people who can record extensive parts of road network. Data entering goes on at home in the quiet environment with a chance of entered data control which means higher quality of data. 4. PRIKAZ PODATKOVNE BAZE V GIS OKOLJU Nadgradnjo podatkovne baze predstavlja pregledovanje in analiziranje zbranih podatkov v GIS okolju, kjer si poleg lastnosti objektov lahko predstavimo tudi njihovo lokacijo v prostoru. Za prikaz uporabljamo programsko orodje ARC/ INFO, kjer na osi ceste oziroma ob njej prikazujemo raz­ lične objekte iz baze. Za podlogo običajno uporabljamo skenirane karte od meril 1:5000 do 1:50000, odvisno od potreb uporabnika sistema. Uporabljamo lahko tudi vse druge prostorske digitalne baze, ki trenutno že obstajajo za določen prostor (obrisi naselij, gozdov, vode, ROTE, EHIŠ, itd.). Seveda pa nam GIS poleg vizualizacije lege objektov omogoča tudi stalen dostop do vseh atributivnih podatkov o teh objektih. 4. DATABASE UPDATE Special problem also represents maintenance such an extensive database. Base without proper maintenance loose its value very fast. We can make the database to be up to date only with constant data entering at local road work performer. For that manner the simple system is made for database managing that enables adding, chang­ ing, deleting of data and simple analysis. At the same time it also records all the history of changes in the database. Immediately after capturing the data on the basis of re­ cordings at certain area, the database is transferred to local manager who then maintains that base and medi­ ates data to common database in regular time intervals. Only with that way we can expect the common database Pri pregledovanju lahko kot dodatno informacijo uporabimo tudi video posnetek, ki smo ga naredili za potrebe vnosa podatkov. Imamo dve možnosti uporabe. Prva je, da se skupaj z video posnetkom premika tudi oznaka na osi ceste, ki prikazuje trenutno lokacijo video posnetka; na ta način lahko enostavno pregledujemo stanje na odseku preko video posnetka. Druga možnost pa je, da z miško izberemo določeno lokacijo na odseku, ki nas zanima in dobimo tudi video posnetek na tej lokaciji (stoječa slika), ki ga lahko potem poljubno premikamo naprej in nazaj; na ta način lahko npr. preverjamo vidljivost v določeni krivini. 5. VZDRŽEVANJE PODATKOVNE BAZE Poseben problem predstavlja tudi vzdrževanje tako obsež­ ne podatkovne baze. Baza brez ustreznega vzdrževanja kaj hitro izgubi vso svojo vrednost. Njeno ažurnost lahko zagotovimo le s sprotnim vnosom podatkov pri lokalnem izvajalcu del na cesti. Za ta namen je izdelan enostaven sistem za upravljanje podatkovne baze, ki omogoča vnos, spreminjanje, pregledovanje podatkov in enostavne ana­ lize, hkrati pa vodi tudi zgodovino vseh sprememb v bazi. Takoj po zajemu podatkov na podlagi posnetkov na nekem območju se baza prenese k lokalnemu upravljalcu, ki potem vzdržuje to bazo in posreduje podatke v skupno bazo v rednih časovnih intervalih. Le tako lahko pričaku­ jemo ažurno skupno bazo. Jasno pa je, da na tak način ni možno rešiti problema zastaranja video posnetkov, zato je potrebno izvesti ponovno snemanje vsakih nekaj let, predvsem na odsekih, kjer je veliko sprememb. 6 . PRAKTIČNA UPORABA SISTEMA Sistem je razvit in izdelan v celoti in je bil operativno uporabljen na projektih Kataster signalizacije in opreme cest ter Kataster obcestnih objektov za potrebe Repub­ liške uprave za ceste. Projekta obsegata popis vertikalne signalizacije, horizontalne signalizacije (vzdolžne, prečne, oznake v križiščih), varnostnih ograj, protihrupne zaščite, svetlobno signalnih naprav, javne razsvetljave, muld, korit­ nic, jarkov, kanalet, brežin, preglednih berm, parkirišč ter lokacij priključkov in križišč za magistralno in regionalno cestno mrežo (prek 4500 km). Izvedeno je bilo tudi že šolanje vzdrževalcev podatkovne baze po posameznih cestnih podjetjih, kjer je baza že vnesena in se koristno uporablja. 7. SKLEP V članku je predstavljena možnost uporabe različnih sodobnih informacijskih orodij (GIS, video, GPS), poveza­ nih v učinkovito celoto. Računalniško podprti video sistem kot celota bistveno prispeva k uspešni nastavitvi prostor­ skih baz podatkov in njihovi uporabi ter s tem bodočim uporabnikom omogoča učinkovitejše gospodarjenje s svo­ jim prostorom in objekti v njem. Sistem je preizkušen s tekočim delom na obsežnem projektu državnih cest. Alternativa je v razvoju video sistema na raven avto­ matskega prepoznavanja obcestnih objektov in določanje natančne lege objektov rja cestišču in ob njem s pomočjo stereo video slike. to be up to date. But it is also clear that it is impossible to solve the problem of aging of the video recordings on that manner. That is why it is necessary to make recordings every couple of years, especially on the segments where one can find a lot of changes. 5. PRESENTING DATA IN ARC/INFO ENVIRONMENT Database upgrade represents controlling and analyzing of collected data in GIS space, where one can represent location of the objects in this space, and also properties of the objects. We use ARC/INFO software, where we show different objects from the base on the axis of the road. For background we usually use scanned maps of measuring scale from 1:5000 to 1:50000, depends what are the needs of the system user. We can also use other different space digital bases that right now already exist for certain area (shapes of settlements, woods, water, territorial units, houses centroids, etc.). Of course, besides objects posi­ tion’s visualization, GIS also enables constant access to all attributive data about these objects. We can use video picture, made for the use of data enter­ ing, as additional information when the data is presented. We have two ways of use. The first one where the sign on the axis of the road, which shows momentary location of video picture, moves together with video picture; we can simply observing the condition on the fragment over the video picture. And the second one where we choose with the mouse certain location on the road that is in interest and we get the video picture on this location (frozen pic­ ture) which can be later optionally moved forward and backward; we can check visibility in certain curve for in­ stance. System is developed entirely, and right now it is operative on the project called KATSIG - Inventorisation and Man­ agement System for Road Signalization and Equipment for Slovenia road administration. Project includes list of vertical signalization, horizontal signalization (longitudi­ nal, transverse, signs in the crossroads), protective guard rail, noise barriers, traffic lights, public lightning, parking and locations of connections and crossroads for primary and secondary road network (over 4500km). Education of database maintainers through particular road companies, was already accomplished. Along the software installation at particular road companies, the test database was also installed which is used for education of new users, and its purpose is to decrease possibilities of unwanted mistakes later. 7. CONCLUSION This article represents the possibility for using different information tools (GIS, video, GPS) connected in the ef­ fective whole. System as a whole essentially contributes to successful settings of space databases and their use. Users are enabled to manage more efficiently with their space and objects. System is tested through fluent work based on extensive project of national roads. 6 . USING THE SYSTEM NASTAJANJE SLOVENSKIH SM ERNIC ZA PROJEKTIRANJE CEST FORMING A NEW SLOVENIAN ROAD-DESIGNING DIRECTIONS UDK: 656.1 (497.12):625.7/.8 ALOJZ JUVANC* V prispevku so predstavljene ovire in razlogi, ki so preprečili, da bi dosedanji YU-Pravilnik za projek­ tiranje cest enostavno samo dopoln ili in minimalno popravili in ga razglasili za nov slovenski tehniški predpis. Zaradi spremenjenih pogledov na izrabo prostora, kreiranje cest in upravičenost investiranja je b ilo treba izvesti dodatne predhodne raziskave. Z njim i so bila opredeljena nova izhodišča za dimen­ zioniranje cestnih elementov ter ugotovljene mož­ nosti za njihovo racionalizacijo. Na teh osnovah pripravljamo predlog novih Smernic za projektiranje cest. Tokrat predstavljamo predvsem tiste določbe, ki so bistveno drugačne od dosedanjih. UVOD Težnje po posodobitvi predpisov za projektiranje cest so prisotne v slovenski javnosti že več kot 10 let. Že več delovnih skupin se je ukvarjalo s tem, vendar do nekih oprijemljivih rezultatov niso prišle. S slovensko osamo­ svojitvijo so se razmere spremenile. Novi predpisi so naenkrat dobili poleg strokovne še državotvorni pomen in Družba za raziskave v prometni in cestni stroki je poverila nalogo priprave predloga Prometnotehničnemu inštitutu FAGG (sedaj FGG). Prva zamisel je bila, da bi enostavno samo nekoliko popravili in dopolnili dosedanji jugoslovanski Pravilnik za projektiranje cest (dalje v tekstu YU-PPC), ki mu ni moč očitati velikih pomanjkljivosti. Je namreč zelo pregleden S U M M A R Y We present the obstacles and the reasons that pre­ vented that the existing YU-Road Designing Rule- book was not simply fu lfilled and corrected and as such accepted as a new Slovenian rule-book. Due to changed public opinion about land-use, road creation and economy of investments additional re­ search was executed. So, new statements for road technical elements dimensioning and its rationalisa­ tion was established. These statements are now the base for the preparation of new Road Designing Directions. In this paper only the directions that are different to the existing ones are introduced. INTRODUCTION Tendencies for the updating the road designing regula­ tions have been present in Slovenia for more than 10 years. More working groups dealt with this problem but they have not found reasonable results. The independ­ ency of state Slovenia brought new impact to this prob­ lem. The new Rule-book became very important besides being a professional also as the state forming meaning. PTI (Traffic Technical Institute) at FAGG was authorized to prepare the proposal of rules. At start the suggestion was only to correct the existing Yugoslav Road Designing Rule-book (shorter YU-PPC) which is just perfect. It is clear and its rules are under­ standable. Due to strong changes in philosophic aspect AVTOR: Doc. dr. Alojz Juvane, dipl. gr. ing. Ass. Prof. Alojz Juvane, Ph. D. in njegova določila korektna. Kljub temu pa je bilo treba to zamisel kmalu opustiti, ker se je v Sloveniji v zadnjem obdobju korenito spremenila filozofija odnosa do zado­ voljevanja prometnih potreb. YU-PPC je bil namreč se­ stavljen izključno na pogojih zagotavljanja prometne var­ nosti, medtem ko so pri nas prišli v ospredje še drugi pomembni pogoji: zaščita naravnega in bivalnega okolja, omejevanje hitrosti in racionalno investiranje v ceste. Pri tem miselnem zasuku so postala določila YU-PPC zaradi svoje enostranskosti in togosti prava ovira. Celoten postopek priprave novega PPC se je zato spre­ menil. Da bi lahko njegova določila čimbolj razjasnili in utemeljili, smo predhodno izvedli posebno raziskovalno nalogo. Rezultati raziskave so temelj za pripravo Smernic za projektiranje cest (nadalje v tekstu SPC), ki bodo sestavni del novega slovenskega PPC. V tem prispevku želimo pokazati potek in rezultate pred­ hodnih raziskav, pojasniti obseg in grobo vsebino novih smernic (SPC) ter opisati in pojasniti tista določila, ki so bistveno drugačna od dosedanjih. PREDHODNA RAZISKAVA Preveritev ustreznosti oziroma zadostnosti določil seda­ njega YU-PPC, izvedba primerjave teh določil z določili v tujih tehniških predpisih in raziskava možnosti za racio­ nalizacijo cestnih elementov so bile izdelane pod skupnim naslovom “Možnost racionalizacije gradnje cest z vidika projektiranja”. Med delom se je pokazala potreba po funkcionalni ločitvi te naloge na tri zaporedne dele, ki so bili vsak posebej obdelani v poročilih. Podnaslovi teh poročil so RACIPROC (julij 1990), OPTIPROC I. (maj 1992) in OPTIPROC II. (julij 1993). Najpomembnejša spoznanja iz raziskave RACIPROC V prvem delu (RACIPROC) smo raziskali ustreznosti določil dosedanjega YU-PPC, izvedli primerjavo s tujimi tehniškimi predpisi in preverili možnosti racionalizacije tehničnih elementov cest. Interesi investitorjev in upo­ rabnikov cest so glede sodobnosti predpisov in racio­ nalizacije zelo podobni, saj smo uporabniki skozi proračun končno tudi investitorji. Najpomembnejši med interesi so: • • kakovostna izraba prostora (kompleksno upoštevanje interesov vseh vrst izrabe) • vplivi na okolje (ohranjanje in zaščita naravnega okolja) • poraba energije (zmanjšanje porabe, kar je tako ekološki kot okoljevarstveni cilj) • prometna varnost (splošen in vsestranski interes) • ekonomičnost investicij (investirati v sorazmerju z real­ nimi potrebami in z optimalnimi stroški) • mobilnost (prosta izbira prometnih sredstev) • socioekonomičnost (skladen sociološki in gospodarski razvoj cele države in dostopnost dobrin) • kakovost ceste (udobnost, čas potovanja, zagotavljanje trajnosti konstrukcije, zunanji videz) • enotni tehniški predpisi za vse javne ceste (ne samo za državne). Glede na te interese smo v YU-PPC ugotovili naslednje pomanjkljivosti: for traffic needs fulfillment in Slovenia we dropped this idea. Why? YU-PPC was formed completely on the base of the traffic safety. So other important conditions like nature and environmental protection, speed restrictions and rational road investments were not observed. We can say that YU-PPC appeared one-sided and rigid and as such an obstacle for up-to-date designing. The whole procedure for the preparation of a new PPC changed. To make the regulations as clear and as founded as possible a special research work was done. The results are the bases for the preparation of Road Designing Di­ rections (in the following text SPC) which are a technical part of a new Slovenian Road Designing Rule-book (PPC). In the following text we would like to show the procedure and the results of previous research, to explain the extent and the rough content of SPC as well as to describe and explain those directions that differ from the previous ones. PREVIOUS RESEARCH Checking the suitability or sufficiency of directions of the existing YU-PPC, the comparison of these directions with foreign technical regulations and the research of the pos­ sibility for rationalization of road elements were done un­ der the common title “The possibilities of the rationaliza­ tion of road construction from standpoint of designing”. During this work the need for functional separation of the work on three successive parts appeared.They were sepa­ rately dealt in reports. The subtitles of them are RACIP­ ROC (July 1990), OPTIPROC I (May 1992) and OPTI­ PROC II (July 1993). The most important findings from RACIPROC « In RACIPROC we investigated the suitability of the exist­ ing YU-PPC, we compared them with foreign technical regulations and we checked the possibilities for rationali­ zation of technical road elements. The interests of inves­ tors and road users are very similar regarding the updat­ ing and rationalisation, as the road investments are the budget costs. The most important interests are: • quality land-use (complex consideration of interests of all kinds of use) • environmental impact (to save and to protect the nature) • energy consumption (reduction of consumption, which is ecological and environmental preserving aim) • traffic safety (common and all concerning interest) • economy of investments (to invest in correlation with real needs and with optimal expenses) • mobility (free choice of traffic means) • socioeconomy (equivalent sociological and economic development of the whole state) • road quality (comfort, traveling time, reassuring of per­ manency of construction, outer appearance) • unique technological regulations for all public roads (not only for the state roads) Considering all quoted above YU-PPC has the following deficiencies: • upoštevani so izključno samo pogoji zagotavljanja pro­ metne varnosti in prepustnosti ceste • veljajo izključno le za ceste zunaj naselij • ne loči med različnimi funkcijskimi vrstami cest (kakovost in vsebina ureditev - kategorija) • ne obravnava prometnega dimenzioniranja ceste • dimenzije tehničnih elementov so odvisne izključno od vnaprej določene računske hitrosti, ki je odvisna od prometne obremenitve in vrste terena • opredeljuje izključno samo mejne vrednosti dimenzij tehničnih elementov osi ceste in cestišča • ne pozna pojmov potovalne hitrosti, projektne hitrosti, maksimalni vzdolžni nagibi so pri enakih terenskih po­ gojih različni za različne prometne obremenitve, ne opre­ deljuje mejnih vrednosti za kritične elemente pri velikih objektih (viadukti, predori, križišča), pa tudi merodajna prometna obremenitev ni opredeljena • nesodobna so določila o koeficientu drsnega trenja, o določitvi zaustavne dolžine in o določanju velikosti para­ metra prehodnice pri voznodinamično kreirani trasi Prva ugotovitev v raziskavi je bila, da pojma racionalizacije ne gre enačiti s'pojmom zniževanja pogojev in zahtev za tehnične elemente osi in profila ceste, kot je bilo sprva predlagano. Voznodinamični in prometni pogoji so ne­ dvoumno odvisni izključno samo od računskih hitrosti. Vprašanje racionalizacije tehničnih elementov se tako skrči na vprašanje določevanja teh hitrosti. Te pa ne morejo biti odvisne izključno samo od prometne obremenitve in vrste terena kot dosedaj, ampak morajo odsevati še vse ostale interese v prostoru in izhajajo iz prometne funkcije po­ samezne cestne povezave in možnosti v prostoru, po katerem cesta poteka. Torej je racionalno, da v primeru dveh prometno enako obremenjenih cest, ki na enako razgibanem terenu povezujeta dva prometno različno močna prometna cilja, uporabimo za dimenzioniranje različni računski hitrosti. Prometno različno pomembnim cestam je torej možno prisoditi povsem različne potovalne hitrosti. V smislu racionalizacije je treba torej vse ceste ustrezno razporediti - kategorizirati - in jim prisoditi katego­ riji primerne potovalne (in druge odvisne) hitrosti. Nadalje smo ugotovili, da je racionalizacija posameznih tehničnih elementov sicer možna, vendar le v primeru, da obstajajo razlogi za to. Najdemo jih v psihofizičnih odzivih uporabnikov cest, ki so na cestah z različnimi prometnimi funkcijami precej različni. Voznik na daljinski cesti se drugače odziva na cestne pogoje kot voznik na neki regionalni povezavi ali v domačem okolju na lokalni cesti. To spoznanje omogoča, da se racionalizira tudi druge parametre, ki odločilno vplivajo na dimenzije cest. To sta predvsem dopustni delež koeficienta drsnega trenja in reakcijski čas. Seveda je spet predpogoj pravilna razpo­ reditev cest v omrežju. Nedvoumen zaključek raziskave RACIPROC je, daje treba racionalizacijo pri gradnji cest iskati skoraj izključno v pravilni razporeditvi (kategorizaciji) cest v cestnem omrežju in dimenzije cest prilagajati predvsem njihovi prometni funkciji v prostoru. To pomeni, da ne moremo govoriti samo o racionalizaciji temveč o optimizaciji tehničnih elementov. • only conditions for reassuring traffic safety and level of service are taken into consideration • they are valid only for rural roads (state-roads) • it does not differ among various functional kinds of roads (quality and category) • it doesn’t count traffic dimensioning of the roads • technical elements dimensions depend only on fixed design speed in advance (based on traffic volume and kind of terrain) • defines only limit values of technical element dimen­ sions of the axis and the roadway • it doesn’t know the expressions like travel speed and design speed, maximum longitudinal grades are differ­ ent at equal terrain conditions for various traffic volumes, limit values for critical elements concerning huge ob­ jects (viaducts, tunnels, cross-roads) are not fixed, and traffic dimensioning is not defined • the definitions of friction coefficient, stopping distance and the definition of length of transition curve at drive- dynamic designed road are old fashioned. The first finding out of the research was that the term rationalization can not be identical with the term of lower­ ing the conditions and demands for the technical ele­ ments of axis and road profile, which was neglected ini­ tially. Drive dynamic and traffic conditions are depending of design-speed only. So the question of technical ele­ ments’ rationalisation is reduced then to the question of speed definition. The speed can not be dependant explic­ itly from the traffic volume and the kind of terrain as prac­ tised, but they must reflect also all other interests in the physical space. It origin from traffic function of a single slip road and of the possibilities in the landscape where it courses. It is nonsense to build up two roads of the same traffic volume with the same technical dimensions when its traffic functions are quite different (arterial and loco). In sense of rationalization all roads need to be suitably ranked - categorized - and must get suitable category depended driving speeds. Further it was observed that the rationalisation of indi­ vidual technical elements is possible only, if very strong reasons exist. They can be found in psychophysical re­ sponses of drivers, which are very various on the roads with various traffic functions. A driver on a heavy duty road responds differently on road conditions than a driver on a local road of a home place. This finding enables rationali­ zation of other parameters which decisively effect on road dimensioning like acceptable part of the coefficient of friction and drivers’ reaction time. In this case the correct categorization is the most essential factor. The obvious result of RACIPROC research is that the realization at road construction must be almost explicitly found at correct road categorization and the dimensions of road elements must be adapted to suitable traffic func­ tion. This means that we can not talk only about rationali­ zation but also about optimization of technical elements of the roads. Najpomembnejša spoznanja iz raziskave OPTIPROC o kategorizaciji in tehničnih elementih Zato smo izdelali še študijo OPTIPROC, ki je v svojem I. delu obravnavala razloge in pogoje za novo kategorizacijo cest ter od nje odvisne racionalne dimenzije elementov cest v tlorisu in v profilu, v II. delu pa odvisnost dimenzij cest glede na stvarne prometne potrebe. Sedanja razvrstitev cest v cestni mreži Slovenije (leta 1988) je bila izdelana na podlagi t.i. geopolitične razdelitve cest. Razvrstitev obsega 6 kategorij: avtoceste (AC), magistralne ceste (M1 in M2) in regionalne ceste (R1 in R2) v pristojnosti republike ter lokalne ceste (L) v pristoj­ nosti občin. Pri tej kategorizaciji je bila najpomembnejši kriterij količina in vrsta prometnih obremenitev. Vendar se je od tega kriterija zelo pogosto odstopalo, kar kaže na podrejenost razvrščanja v kategorije političnim interesom lokalnih skupnosti (občin). Zlasti je to opazno pri uvrščanju cest v kategoriji M2 in R1. Tja so bile uvrščene tudi ceste, ki največkrat niso presegale funkcije lokalnih povezav in imele, v nasprotju s kriteriji, zelo skromno prometno obremenitev. Ker so bile vse ceste dimenzionirane samo na podlagi prometa in terena (YU-PPC), so nastale izredno velike razlike pri dimenzijah in zunanjemu videzu cest v isti kategoriji. Očitno je bil poglavitni cilj dosedanje kate­ gorizacije določevanje prioritete pri vzdrževanju in obnav­ ljanju cest ter zagotavljanju prevoznosti. Zato kategorija ceste sama ni imela nobenega vpliva niti na videz ceste in še manj na njene dimenzije, kar je v svetu normalno. Raziskali smo pojem kategorije ceste. Kategorija ceste je določena vrsta ceste, ki z ustreznimi lastnostmi pri poteku skozi prostor omogoča izvajanje določene prometne funk­ cije; od najpomembnejše do najmanj zahtevne. Glede na vrsto prostora, po katerem poteka, so vzdolž ceste iste kategorije možne različne tehnične, gradbene in oblikovne rešitve. Te rešitve so zaradi različne pomembnosti cest pri različnih kategorijah različne. Zato smo uvedli pojem kakovosti ceste, ki ga opredeljujejo splošni strokovni kriteriji in družbeno verificirani atributi, prisojeni posamezni kategoriji ceste. Splošni strokovni kriteriji za zagotavljanje različnosti med kategorijami cest so: • prometna funkcija (daljinsko povezovanje, povezovanje, zbiranje in dostop) • čas potovanja (potovalna hitrost, psihofizične lastnosti voznikov, zamude, tekoča vožnja in ustrezna kakovost uslug na cesti) • vodenje skozi prostor (zunaj naselja, skozi naselje - obzidano, neobzidano) • prometni režim (omejevanje uporabe, diferenciranje pri­ ključevanja drugih cest, ureditev križišč, dimenzioniranje profila cestišča, definiranje dopustnih hitrosti) • varovanje in ohranjanje okolja (koncentracija težkega in sploh prometa na pomembnejših smereh, opredelitev stopenj zaščite, različnost pristopa pri projektiranju, pomembnost vpliva posameznih prostorskih omejitev) • vodenje prometa (zahtevnejša ali skromnejša oprema ceste, kontinuiteta vodenja pomembnejše smeri v kri­ žiščih ipd) The most important findings from OPTIPROC about categorization and technical elements OPTIPROC in its first part deals with the reasons and conditions for a new road categorization and with the dependence of rational dimensions of road elements in layout and in profile. In its second part the research deals with the dependence of road elements dimensions re­ garding to actual traffic needs. The existing road categorization in Slovenia was done in 1988 on the ground of so called geopolitical road division. It consists of 6 categories: motorways (AC), major roads (M1 and M2), regional roads (R1 and R2) under the au­ thority of the State and local roads (L) under the authority of the community. The most important criterion was the quantity and structure of traffic volume. Because of politi­ cal interests of loco communities this criterion was very often neglected. It was very obvious at road categories M2 and R1 where some roads were ranked higher than the criteria allowed. The dimensioning, related only to traffic volume and terrain, caused great differences at dimensions of the elements and at outlook of the roads of the same category. Obviously the main aim of former categorization was the determination of priority at road maintenance and reconstruction and to assure the pas­ sably. That is why the category itself did not have any influence on road outlook and dimensions of the elements what is normal in the developed countries. First of all the term “category” was researched. The cat­ egory of road is a definite kind of a road which with some suitable characteristics at its course through the land­ scape makes some traffic functions possible - from the last to the most demanding. Regarding the kind of land­ scape where it lies, all along the roads of the same cat­ egory various technical, constructive and outlook solu­ tions are possible. They differ from a category to a cat­ egory. That is why we introduced the term “road quality” that is defined by general professional criteria and socially verified attributes added to each road category. General professional criteria to assure the differences among categories are: • traffic function (long distance, connection, collection and access) • travel time (travel speed, psychophysical drivers’ abili­ ties, delays, current traffic flow, convenient level of serv­ ice) • tracing through the landscape (rural or urban roads) • traffic regime (restrictions of the use, differentiation of connections, type of cross-roads, dimensioning of the elements of road cross-section, acceptable speeds) • protection and preservation of the environment (concen­ tration of heavy traffic on the main roads, step of protec­ tion, difference in designing, importance of the influence of landscape restrictions) • traffic control (the quality of the equipment of road, conti­ nuity of the main traffic flow in the crossings) According to these criteria the different dimensions of road elements and its outlook are defined. The step of quality for these parameters, awarded to each category of roads, depends of professional and general social deci- Po teh kriterijih se za različne kategorije cest določijo različne dimenzije elementov in njihov zunanji izgled. Kako zahtevne naj bi bile izvedbe pri posamezni kategoriji pa je odvisno od strokovne in splošne družbene odločitve. Vse tovrstne odločitve so za posamezno kategorijo cest obveza in predstavljajo njen tehnični in/ali urejevalski pogoj - atribut. V raziskavi smo predstavili 7 različnih skupin atributov, dodatne predloge pa pričakujemo Iz javne obravnave: • funkcionalnost ceste (povezovanje v mreže, dopustnost priključevanja cest nižjih kategorij, dopustnost infra­ strukturnih vodov v cestnem telesu, časovna dosegljivost ciljev, dopustnost nivojskega križanja z železnico ipd) • prometne lastnosti (vrste uporabnikov, delež vozil v relativnem tranzitu, zagotavljanje prioritete vzdrževanja in obnavljanja ipd) • prometna varnost (dopustna vozna hitrost, obveznost preverjanja voznodinamične ustreznosti ceste, dopustna prometna obremenitev, zahteva po ločenih voziščih za vsako smer vožnje, minimalne dimenzije elementov prečnega profila in dopustnost združevanja različnih uporabnikov, dopustnost različnih vrst združevanja teko­ čega in mirujočega prometa, vrsta in opremeljenost kri­ žišč, gostota in način priključevanja nekategoriziranih cest in individualnih lokacij, obseg in zahtevnost ter zna­ čilnost opreme na cesti ipd) • ekološka vplivnost (različnost podrejanja ali prednosti pred zahtevami za varstvo in ohranjanje okolja, stopnja izvedbe zaščite ipd) • tehnični parametri (možne računske hitrosti, dopustna izraba keoficienta drsnega trenja v radialni smeri, obvez­ nost uporabe prehodnice, stopnja skladnosti zaporednih geometrijskih elementov, stopnja zagotavljanja čimbolj enakomerne vozne hitrosti, reakcijski čas, rezervacija ceste samo za motorni promet ipd) • ekonomičnost (stopnja prometne izkoriščenosti - raven uslug, faznost gradnje, trajnost konstruktivnih elementov, zahteva po izračunu ekonomičnosti ipd) • planske karakteristike (prioriteta zimske službe, prioriteta vzdrževanja in obnavljanja ipd) Prometne obremenitve, ki je bila v dosedanji kategorizaciji zelo pomemben kriterij, tukaj ne najdemo, ker nima nepo­ srednega vpliva na funkcionalnost cestne smeri. Vpliva namreč samo na dimenzije ceste v prečnem profilu in po potrebi na povečanje dimenzij elementov cestne osi zaradi zagotavljanja prepustnosti. Vsak drugačen pristop pomeni negospodarno obnašanje. Za izvedbo kategorizacije se v stroki uporabljata funk­ cionalna in prostorska klasifikacija. Pri tem je dopustno in racionalno, da se v primeru močno različnih zahtev in možnosti uvedejo še podkategorije. Različnim podkatego- rijam cest je potem možno prisoditi diferencirane tehnične zahteve in pogoje. Za razvrščanje posameznih prometnih smeri v posamezno kategorijo je treba upoštevati: • • kategorizacijske kriterije (pomembnost smeri, prostorsko razsežnost, vrsto prometne funkcije in delež relativnega tranzitnega prometa) in • omejitvene kriterije (zgoščenost cest v cestni mreži, dopustna kategorija vzporednih cest in reliefne omejitve). sion. All these decisions become the obligation and can be considered as technical or designing conditions - at­ tributes. In our research-work we have suggested 7 differ­ ent attributes: • functionality of the road (forming of road-nets, lower category connections, infrastructure objects in road cross-section, considerable travel time between neigh­ bour urban centers, allowance of level railway crossings) • traffic features (type of users, share of vehicles in rela­ tive transit, priority of maintenance) • traffic safety (speed limitation, obligatory checking of drive dynamic suitability of the road, traffic volume, de­ mand for the separation of the carriageway, minimal element dimensions of cross-section and allowance of various users implementation in it, kind and equipment of crossroads, density and the mode of points of access of non-categorized roads and individual locations, quan­ tity and quality of the equipment on the road) • ecological influence (higher or lower, different steps of protection and preserving) • technical parameters (possible design speed, allowed value of friction coefficient in radial direction, obligatory use of transition curve, step of coordination of succes­ sive geometrical elements, assuring of the most equal drive speed along the road, driver’s reaction time) • economy (level of traffic exploitation - level of service, phase build-up possibility, demand of durability of con­ struction elements, demand for economical calculation) • planning characteristics (winter service priority, mainte­ nance and re-building priority) Traffic volume, which was very important criterion in the former categorization, is not present in these criteria and attributes, because it does not have a direct influence on the functionality of a road direction. It has its influence only to the number and dimensions of traffic lanes and if necessary for increasing of dimensions of road axis ele­ ments to assure the flow. Any other treatment will be considered as uneconomical. To realize the categorization in practice a functional and landscape classifications are used. It is rational and ac­ ceptable that in case of strongly different demands addi­ tional sub-categories can be introduced. For the ranking of the roads in the road-nets following criteria are to be considered: • criteria of categorization (importance of the connection, spacious extensivity, kind of traffic function, share of relative transit traffic) and • restrictive criteria (density of roads in road-net, allowed category of parallel roads, relief restrictions) A sample of a new road categorization was achieved. The quality of each category was presented with suitable at­ tributes, different for rural and urban roads. We also sug­ gested the naming of the roads of individual category, when passing the urban zone. The graphic presentation (map) was shown too. The basic attribute of each cat­ egory is the travel speed, which in connection with defined traffic flow and restrictions in the landscape identify so called design speed, to which all dimensions of the ele­ ments are related. Due to different demands of traffic function all other influential parameters (friction, reaction) V študiji smo izdelali konkreten predlog nove kategorizacije cest, z atributi pokazali kakovost posamezne kategorije v zunajurbanem in urbanem prostoru, predlagali poimeno­ vanje cest v urbanem prostoru, ki ustreza posamezni kategoriji in izdelali grafični prikaz. Osnovni atribut je potovalna hitrost, ki v povezavi z opredeljeno prepustnostjo in omejitvami v prostoru opredeljuje t.i. računsko hitrost in s tem dimenzije tehničnih elementov cest. Različne stop­ nje zahtevnosti drugih vplivnih parametrov (trenje, reak­ cijski čas), ki dodatno vplivajo na velikost teh dimenzij, so pri tem odvisne od zahtevnosti prometne funkcije. Vse ostale odvisnosti so pogojene s fizikalnimi zakoni in vozno dinamiko in tega ni možno spreminjati. Najpomembnejša spoznanja iz raziskave OPTIPROC o dimenzijah vozišča Dimenizije širine vozne in njej vzporednih površin so odvisne predvsem od prometne obremenitve in z njo povezane prepustnosti, prometne varnosti in gospodar­ nosti in le posredno vplivajo na višino vozne hitrosti. Določilo YU-PPC, da je širina voznega pasu odvisna izključno od računske hitrosti, ni sprejemljivo. Tuje raziska­ ve (Koppel, Nemčija) in domača opazovanja so pokazala, da je vozna hitrost na cesti odvisna predvsem od iztegnje- nosti posamezne trase in seveda od gostote prometnega toka in bolj malo od same širine voznega pasu. Nasprotno pa večja širina voznega pasu omogoča svobodnejšo izbiro vozne linije v krivinah (“sekanje” ovinkov) in s tem večjo iztegnjenost trase ter višjo hitrost. Nepotrebno široki vozni pasovi so torej neracionalni in v nasprotju z načelom omejevanja voznih hitrosti, ki je že dalj časa prisotno po vsem svetu. Odvisnost širine voznega pasu od prometne obremenitve ni posebej izrazita. Ugotovljeno je, da širine nad 3,50 m skoraj ne prispevajo povečanju prepustnosti, medtem ko je znatno zmanjšanje prepustnosti (nad 15%) opazno šele pri širinah voznih pasov pod 3,0 m. Nekaj temu prispeva še vzdolžna ureditev ob vozišču (bankina), vendar ne bistveno. Zato večina držav sedaj opušča širino voznega pasu 3,75 m in uveljavlja kot največjo širino 3,50 m. V ZDA je največja širina voznega pasu določena na 3,65 m. Ni razloga, da bi v Sloveniji ravnali drugače. Vpliv širine voznega pasu na prometno varnost gotovo obstaja. Vendar so pri tem neke značilnosti. Bistvene razlike med stopnjami prometne varnosti pri širinah med 3,25 m in 3,75 m ni. Pri ožjih voznih pasovih se ta stopnja poveča, če je prisoten velik delež težkih vozil, sicer pa ne. Najbolj značilno pa je, da je ta stopnja precej večja od običajne pri sorazmerno majhni prometni obremenitvi (pod 5000 vozil/dan). Temu so vzrok višje vozne hitrosti vozil v prostem prometnem toku. Trditev, da je širši vozni pas prometno varnejši, torej ne drži vselej! Širina voznih pasov naj bi bila zato odvisna predvsem od kategorije ceste in strukture prometne obremenitve ter oblike izvedbe obcestja. Za primer: dvignjen robnik zahteva širino voznega pasu najmanj 3,25 m, če so v strukturi prometa tudi redni avtobusi ali znatno število težkih vozil. Vsako dodatno širjenje voznih pasov je pogojeno izključno le z zahtevano prepustnostjo. additionally effect on the size of these dimensions. All other relations are regulated by physical laws and drive dynamic and can not be changed. The most important findings from OPTIPROC about carriageway dimensions The width of a road surface and parallel areas are de­ pendant from traffic volume, capacity, traffic safety and feasibility of the road. They have only indirect effect to the height of driving speed. Foreign research (Koppel, Ger­ many) and our observations proved that the driving speed depends above all on extension of individual trace and on density of traffic flow and less on the very width of a lane. On the other side larger width of a traffic lane enables freer choice of driving line in curves (“cutting” the curves) that causes larger extension of trace. Higher speed is a normal result. Unnecessary wide driving lanes are illogi­ cal and in the opposition to the principle of driving speed reduction, which is very actual for some time. The dependence between the width of a lane and traffic volume is not extra evident. It is found out the widths above 3,5 meters contributed hardly anything to increase the capacity. On the other hand a greater decrease of capacity is evident with the widths under 3,0 meters. The shoulder contributes in some extent, but not essentially. So the width of lane 3,75 meters has been slowly drop­ ping in several states and 3,50 meters is being introduced. There is no reason the widths will be different in Slovenia. The influence of the lane-width on traffic safety surely exists. But there are some characteristics. No essential differences among the degrees of traffic safety are found out for the dimensions among 3,25 and 3,75 meters wide lanes. By narrower lanes this degree increases if a great part of heavy vehicles is present. It is the most essential that this degree is much higher at a comparatively low traffic volume (under 5000 v/d). The reason is higher driv­ ing speed in a free traffic flow. The statement that a wider lane is safer is not always valid! The lane width could be dependant from a road category, from the structure of traffic volume and from the form of by-carriageway elements. E.g.: high curb demands at least 3,25 meters wide lane if there are line buses or a consid­ erable number of heavy vehicles on the road. Any addi­ tional widening of lanes depends exclusively to assure the demanded capacity or LOS. The capacity (or service volume) depends on lane width, on the arrangements on sides of a carriageway (obstacles and their distance) and on trace extension (design speed). The basic indicator is “travel speed” where psychophysical abilities of drivers are taken into consideration as well as travel time economy and the lowest quantity of the ex­ haust gases and noise. In connection with defined service volume this speed enables to get the design speed and all the dimensions depended of it. The service volume is well known as traffic flow under certain LOS conditions - travel speed and density of traffic flow. In this parameter also the economy of investment can be found. So we suggest for this parameter a new expression “degree of traffic suitabil­ ity” (SPU). Prepustnost je (bolj malo) odvisna od širine voznih pasov, ureditev ob vozišču (oddaljenost in oblika ovir) ter od iztegnjenosti trase (računske hitrosti). Njen osnovni ka­ zalec je potovalna hitrost, s katero upoštevamo psihofizič­ ne sposobnosti voznikov, ekonomiko časa potovanja in najmanjšo količino škodljivih emisij vozil na posamezni cesti. Ta hitrost v povezavi z opredeljeno stopnjo izkori­ ščenosti kapacitete ceste omogoča, da se določi računska hitrost ceste in z njo vse tehnične dimenzije. Stopnjo izkoriščenosti kapacitete ceste poznamo v stroki kot LOS (level of service - ZDA), ki označuje stopnjo usluge, ki jo cesta nudi Uporabnikom - potovalno hitrost in gostoto prometnega toka. Ker se v tem parametru “skriva” tudi gospodarnost investicije, predlagamo zanj izraz “stopnja prometne ustreznosti” (SPU), saj istočasno zagotavlja predvideno potovalno hitost, dopustno izkoriščenost kapa­ citete ceste in optimalne dimenzije elementov. Da bi zagotovili racionalnost in tipičen zunanji videz cest posamezne kategorije, je treba zanje določiti minimalne in alternativne normalne prečne prereze (NPP). Izdelali smo tak predlog in vzporedno pokazali še ureditve ostalih površin v profilu (obcestje). Le-te so v mnogočem odvisne tudi od možnosti vzdrževanja (n.pr. širina stroja za košnjo v ločilnem pasu) in jih je smotrno poenostaviti in poenotiti. Predlagani NPP za avtoceste so bili medtem že upoštevani v Nacionalnem programu izgradnje avtocest v Sloveniji. Ostali NPP so še v pripravi. PREDLOG NOVIH SMERNIC ZA PROJEKTIRANJE CEST (SPC) Dosedanji YU-PPC je obravnaval samo elemente cestne osi in profila vozišča. Zato smo predlagali, da se izdelajo tudi smernice za izvedbo križišč, servisnih površin ob cestah, odvodnjavanja, obcestja, ekologije pri načrtovanju cest in prometne opreme. Smernice za dimenzioniranje elementov cestne osi in profila, ki jih izdelujemo, so sedaj v strokovni obravnavi na Ministrstvu za promet in zveze. Pri izdelavi predloga smo upoštevali določila predloga novega Zakona o cestah, tuje smernice (Nemčija, Avstrija, Francija, Hrvaška, ZDA) in ugotovitve lastnih raziskav. Poglavja SPC so: 1. Uvodna določila (splošna določila, položaj ceste v prostoru) 2. Razvrstitev cest (upravna kategorizacija, tehnična razvrstitev) 3. Osnove za določitev tehničnih elementov (merodajne hitrosti, voznodinamične količine, voznodinamične zah­ teve, normalni prečni profil, karakteristični prečni profil) 4. Prometno dimenzioniranje (prometna obremenitev, merodajna prometna obremenitev, prepustnost, do­ pustna izraba kapacitete, tipični NPP po kategorijah) 5. Preglednost (zaustavna dolžina, zaustavna pregled­ nost, prehitevalna preglednost, pogoji za zagotavljanje preglednosti) 6. Horizontalni elementi cestne osi (prema, krožni lok, prehodnica) 7. Elementi v podolžnem profilu (niveleta, podolžni nagib, zaokrožitve) To assure the rationality and a typical road outlook of each category, minimal and alternative normal cross-sections (NPP) must be defined. Such a suggestion was found and parallel we showed also the arrangements of by-carriage- ways elements. They are much dependent on the mainte­ nance possibilities (e.g. width of a grass-enter mover in lane separator) and they need simplification and unifica­ tion. The suggested NPP for motorways have already been taken into consideration in the National program for motorways in Slovenia. Other profiles are in preparation. SUGGESTION FOR A NEW APPROACH FOR ROAD DESIGNING The existing YU-PPC was dealing only with elements of center-line tracing. Therefor we suggested that new ap­ proaches for cross-roads designing, service-areas, drain­ age, by-carriageway elements, ecological designing and traffic equipment should be additionally executed. Our proposal for new approach for road designing (SPC) is already in the revision by Ministry of traffic and communi­ cations. Designing this approach we considered definitions for new Slovenian Road Code, foreign directions (Germany, Aus­ tria, France, Croatia, US) and the results of our own re­ searches. The chapters of SPC are: 1. Introductory specifications (general regulations, road and landscape) 2. Road classification (Road Code classification, techni­ cal classification) 3. Bases for determination of technical elements (allowed speeds, drive-dynamic qualities, drive-dynamic de­ mands, normal cross-sections, characteristic cross- sections) 4. Traffic dimensioning (traffic volume, maximum hourly volume, capacity, degree of traffic suitability, typical NPP according to categories) 5. Sight distance (stopping length, stopping sight dis­ tance, overtaking distance, conditions for reassuring sight distance) 6. Horizontal elements of axis (straight, arc, transition curve) 7. Elements in longitudinal profile (nivelete, gradients, vertical alignment) 8. Elements in cross-section of carriageway (kinds of gradients, limit values of gradients in arc, screwing, widening in curves, widening for additional lane) 9. Loop curves 10. Compulsory details (curbs, safety rails) The main characteristic of new SPC is that they are pre­ pared for designing all public roads - urban and rural. To overcome the definitions of the Road Code regarding cat­ egorization that officially classified urban roads differently than rural ones and to notify these categories regarding to types of users (traffic function), we introduced technical road classification. It consists of 4 groups (A, B, C and D) with typical driving-dynamic demands. Group A has the greatest driving-dynamic demands and in the group D are the roads where only passability is to assure, without any driving-dynamic demands. 8. Elementi v prečnem prerezu vozišča (vrste nagibov, mejne velikosti, velikosti v krožnem loku, vijačenje, posebnosti, razširitve v krivinah, razširitve za dodatne pasove) 9. Serpentine 10. Obvezni detajli (robniki, varnostne ograje) Poglavitna značilnost novih SPC je, da so namenjene za projektiranje vseh javnih cest - urbanih in zunajurbanih. Da bi presegli določila zakona o cestah glede kate­ gorizacije, ki upravno razdeli urbane ceste drugače kot zunajurbane, in istočasno te kategorije opredelili glede na tipične uporabnike (glede na prometno funkcijo), smo uvedli tehnično razvrstitev cest. Le-ta obsega 4 skupine (A,B,C in D) s tipičnimi voznodinamičnimi zahtevami (izra­ ba trenja, reakcijski čas, obveznost skladnosti elementov in uporabe prehodnice, prehitevalna preglednost). V skupi­ no A so uvrščene ceste z največjimi voznodinamičnimi zahtevami, v skupino D pa tiste ceste, na katerih je treba zagotavljali zgolj prevoznost brez voznodinamičnih zahtev. Vse po zakonu o cestah določene kategorije cest smo razvrstili v te 4 skupine in jim določili potovalno hitrost in druge voznotehnične lastnosti (vrsta prometa, dopustna hitrost, NPP, tipe križišč in možne zasnovalne hitrosti). Vse hitrosti so določene v razponih in omogočajo projek­ tantu izbiro glede na omejitve v reliefu in prostoru sploh. Pri tem je treba posebej poudariti, da so predlagane dopustne hitrosti take, da odsevajo realna dogajanja in obenem omogočajo normalno izrabo voznih površin v različnih okoljih. Privzet je sistem hitrosti 50, 70, 90, 110 in 130 km/h, ki glede na sposobnosti vozil omogoča uporabo ustreznih prestavnih razmerij pri manjših obratih v motorju. Obenem je to tudi bistvena ekološka prednost. Hrup motorja je tedaj minimalen in emisije plinov v mejah sprejemljivosti. Predlog je v izrazitem nasprotju s pred­ logom novega Zakona o varnosti v cestnem prometu. V SPC je opredeljen postopek za izračun prepustnosti in navedene merodajne količine, ki jih je treba upoštevati kot prometno obremenitev, kadar poseben izračun ni zah­ tevan. Naveden je tudi postopek izračuna za primer uved­ be dodatnih pasov za težka vozila. Dodatni vozni pasovi za težka vozila se na koncu ne zaključujejo (kot sedaj), ampak se tam zaključuje prehitevalni pas. S tem želimo preprečiti težave, ki nastajajo na tem mestu pri vključeva­ nju težkih vozil, ko se gostota prometa na cesti zelo poveča. Seveda je pri izvedbi zaključevanja prehitevalnega pasu upoštevana visoka vozna hitrost in predvideni ukrepi za zagotavljanje prometne varnosti. Za enostavnejšo uporabo so po nemškem vzorcu pokazani za vsako kate­ gorijo cest možni NPP in njim pripadajoče količine pri določeni stopnji izkoriščenosti kapacitete (potovalna hit­ rost, število vozil). Nanovo smo uvedli pojem projektne hitrosti. To je hitrost, ki jo omogočajo dejanski geometrijski elementi ceste (v projektu ali na obstoječi cesti) in jo v stroki poznamo kot hitrost v prostem prometnem toku (Vas%). Običajno se ta pokaže s profilom projektne hitrosti. Navedene so vse obveznosti, ki nastajajo s tem v zvezi. Uvedli smo novo PIARC formulo za največjo dopustno vrednost koeficienta drsnega trenja in izračunali zaustavne razdalje po točni formuli (integral). Odpravili smo doseda- All the categories defined according the Road Code are lined into one of the 4 groups. For each of these groups different travel speed and other driving-technical features (traffic mode, speed limit, NPP, types of crossings, design speed) are defined. All the speeds are defined in spans and allow the designer the choice regarding to the land­ scape restrictions. It is necessary to emphasize that the suggested speed limits reflect the actual happening and allow a normal use of driving areas in different surround­ ings at the same time. The system 50, 70, 90, 110 and 130 km/h was taken which regarding the ability of vehicles allows at the same time the use of available gear relation at lower turnings of the motor. This means the essential ecological advantage. The engine noise is then minimal and the exhaust gases are still acceptable. Our proposal is in great opposition with the proposed new Slovenian Traffic Safety Code. In SPC the procedure for the calculation of capacity is defined as well as the volume quantities that must be considered when a special traffic study is avoided. The procedure for the calculation of additional lane(s) for heavy vehicles is cited. A new suggestion about the finish-part of the additional lane for heavy vehicles is given. Instead of additional lane the overtaking one is ended. We would like to prevent the troubles that arise at the section where heavy vehicles merge to the right lane in the conditions of great density of traffic flow. It is obvious that a very high operating speed on the overtaking lane needs special length of “safety area” to reduce speed and to merge to neighbor lane. To be easily used, following the German sample, all possible NPP, equipped with the quantities of service volume and travel speeds for each category are given. The term of “operating speed” was newly introduced. This is the speed that is actually allowed (in a design or on the existing roads) by geometrical elements of road. In our branch it is known as the speed along the road in free traffic flow conditions (Vas%). Usually it is shown in an operating speed profile. All obligations concerning this speed are quoted. A new PIARC formula for limit value of coefficient of fric­ tion was introduced and new sight distances were calcu­ lated following the exact formula. We abolished the exist­ ing definitions about three possible sight distances (on the dam, normal and STOP) in YU-PPC. It is let to designers to choice and to explain any other value if needed. The definition for overtaking distances was corrected. Mini­ mum lengths were defined as an envelope of minimum possible values for different speeds of vehicles included. A special computer program was prepared for this job. The limit values of all geometrical elements were defined for each technical group separately. So each group has its own value for minimal radii of circle, different transition- curve length and limit down-grade. The latter was defined regarding the designing speed which by itself restricts its maximum value. This maximum value is in the correlation with the friction coefficient and does not depend on traffic volume or terrain conditions as it has been defined in YU- PPC. For all geometrical elements special restrictions for the use in the area of very important objects (viaducts, nja določila o treh možnih zaustavnih razdaljah (na nasipu, normalna in STOP) in prepustili projektantom, da v poseb­ nih pogojih sami utemeljijo drugačne dimenzije. Prehiteval­ no razdaljo smo raziskali s posebnim računalniškim pro­ gramom. Ovojnica najmanjših razdalj, izračunanih pri raz­ ličnih razmerjih voznih hitrosti udeleženih vozil in izrisanih v diagramu, predstavlja minimalne potrebne dolžine. Velikost mejnih geometrijskih elementov smo opredelili za vsako tehnično skupino cest posebej. Na ta način smo dosegli racionalizacijo tehničnih elementov glede na pro­ metno funkcijo, ki jo ima posamezna kategorija ceste. Maksimalno vrednost vzdolžnega nagiba smo opredelili glede na računsko hitrost, ki sama po sebi omejuje njegovo velikost. Posredno je tu upoštevan vpliv koeficienta trenja in ne vpliv velikosti prometne obremenitve ali terenskih pogojev, kot je bilo to v YU-PPC. Za vse geometrijske elemente smo zapisali tudi določila o njihovi uporabi v območju zahtevnih objektov (viaduktov, predorov, križišč ipd), česar vYU-PPC ni. Velikost sedanjega maksimalnega prečnega nagiba v loku smo ohranili in dopustili njegovo izjemno povečanje za 1% (na 8%), kadar pri obnovi obsto­ ječih cest z drugačnim ukrepom ni mogoče urediti vozno- dinamičnih razmer v posameznem krožnem loku. Zaradi uvedbe projektne hitrosti smo izključili možnost proste izbire minimalne velikosti prehodnic. Ker obstaja neposredna voznodinamična soodvisnost velikosti polmera krožnega loka in možne vozne hitrosti na njem, je mini­ malna velikost prehodnice za ta polmer samo ena. Vsake­ mu polmeru torej pripada samo ena minimalna velikost parametra prehodnice. Ta določitev omogoča spremembe v tehnologiji projektiranja cestne osi z računalnikom. Z novimi SPC želimo omogočiti projektantom kreativno delo, investitorjem gospodarno investiranje in uporabnikom prometno varno ter prometnim potrebam ustrezno uporabo ceste, ki naj bi imela na okolje čimmanj kvarnih vplivov. Predvsem pa s temi SPC izenačujemo tehnične pogoje in zahteve na vseh cestah - urbanih in zunajurbanih, saj smo dosedaj projektirali ceste v urbanih okoljih kar po YU- PPC, kar je bilo neracionalno. Izjema je Mesto Ljubljana, ki ima svoj Pravilnik za projektiranje mestnih cest. tunnels, crossings) have been given. The value of existing radial grade of carriageway in arc was obtained. Addition­ ally an extreme increase of 1% (to 8%) was allowed to apply in special conditions of re-building of existing car­ riageway where no other solution is available to avoid driving-dynamic danger in circle. Introducing of an operating speed it is not reasonable to allow completely free choice of minimal length of transi­ tion curve for different radii of circles. There is a direct driving-dynamic connection between a circle arc radius and operating speed in this arc and the minimum length of transition curve is only one - driving-dynamic defined. So each radius of circle has its own length of transition curve. This solution enables new possibilities for the computer created road axis. With a new SPC we wish to enable a quality work of designers, rational investments for the investors and a safe and to traffic needs suitable use of the road with minimum damage to the environment. Above all we want to identify technical conditions and demands on all roads - rural and urban and to get them rational solutions about dimensions and shape. Dušan Fajfar 252 Gradbeni vestnik • Ljubljana (44) PROSTORSKI INFO RM ACIJSKI SISTEM EVROPSKIH AVTOCEST EUROPEAN MOTORWAY UDK: 656.13(4):007.52 DUŠAN FAJFAR*, TOMAŽ KASTELIC, TONE ŽAGAR Konec leta 1994 je mednarodna cestna zveza (IRF - International Road Federation, Geneva, Switzerland) zbrala in izdala osnovne podatke o avtocestnem omrežju v Evropi. V bazi so zbrani podatki o ob­ stoječi in o načrtovani avtocestni mreži. Podatki avtocestnega omrežja obsegajo na primer lokacijo in dolžino avtocestnega odseka, status odseka, števi­ lo voznih pasov, povprečni dnevni promet ločeno za osebna in tovorna vozila, vrsto vozne površine, podatke o prometni varnosti, upravljalca ceste, pri­ oriteto izgradnje načrtovanih odsekov, itd. Vsi po­ datki opisujejo trenutno stanje, prav tako pa je podana tudi napoved za leto 2010. Banka avtocest­ nih podatkov je bila izvedena s programskim pake­ tom MS ACCESS. Zbrane podatke je možno pred­ staviti v oblik i različnih tabelaričnih poročil, dopol­ njenih z ustreznimi grafikoni. Vendar pa uporabnik običajno le s težavo ustvari pravo sliko stanja na avtocestnem omrežju zaradi velike ko lič ine po­ datkov. S prostorsko predstavitvijo podatkov bi banka avtocestnih podatkov dobila novo vrednost. Za ta namen sta IRF in Prometnotehniški inštitut (PTI) Fakultete za gradbeništvo in geodezijo v Ljubljani bazo dopolnila z geografskim informacijskim siste­ mom (GIS). Omrežje avtocest je b ilo digita lizirano in razdeljeno na posamezne odseke v skladu s podat­ kovnim modelom. Za osnovno orodje prostorskega informacijskega sistema smo izbrali programski pa­ ket ARCVIEW. Za ostale prostorske informacije, ki rabijo kot ozadje, smo uporabili publikacijo Digital European Motorway Databank was established by the International Road Federation (IRF), Geneva, Switzerland. Beside the data, which exactly describe the motorway network geometry, different data like status of construction, number of lanes, traffic vo l­ umes, traffic safety data, management and financing data, etc. for present and future situation were co l­ lected for each motorway section. Motorway da­ tabank was implemented by the MS ACCESS. The presentation of the collected data was possible only as different reports, tables, charts, etc. In this way user can get large amount of exact data, but from which is very hard to get clear picture of the situa­ tion on the motorway network. W ith the graphical presentation of the motorway data the databank w ill get new value. For this reason the IRF and the Traffic Technical Institute, University of Ljubljana, Slovenia developed a GIS extension of the Motorway Data­ bank. Motorway network was digitised and segmen­ tation was done according to the database model. As a presentation tool we select ARCVIEW 2.0. For background information o f space we use Digital Chart of the W orld. In this way we get very power­ ful, easy to use and nonexpensive tool to manage and to present the European motorway database. In the May o f 1995 the p ilo t project for Austria and Slovenia was presented at the IRF meeting in Glas­ gow, Scotland where was decided to implement the next step of the project to cover whole Europe mo­ torway network. AVTOR: Mag. Dušan Fajfar, dipl. ing. mat. Dušan Fajfar, M. Sc. Chart of the W orld. Na ta način smo dobili zelo močno, enostavno in ne predrago orodje, ki pomaga pri upravljanju in predstavitvi baze podatkov evrop­ skih avtocest. V maju 1995 je bil na srečanju IRF članov v Glasgowu na Škotskem predstavljen pilotski projekt za območje Avstrije in Slovenije. Projekt je bil zelo pozitivno ocenjen in je prejel vso podporo za razširitev na območje celotne Evrope. UVOD International Road Federation (IRF), Geneva, Switzerland je v nekaj zadnjih letih vzpostavila Banko podatkov evrop­ skih avtocest. Najprej je bil razvit podatkovni model, kjer so se odločili za fiksne avtocestne odseke. S pomočjo lokalnih IRF organizacij v posameznih državah se avto­ cestno omrežje razdelili na odseke in vsakemu odseku določili enoličen identifikator, ki predstavlja ključ dostopa do podatkov za celotno bazo. Za vsak avtocestni odsek so poleg podatkov, ki natančno opisujejo lokacijo odseka, zbrani tudi podatki o status odseka, številu voznih pasov, povprečnem dnevnem prometu ločeno za osebna in to­ vorna vozila, vrsti vozne površine, podatki o prometni varnosti, upravljalcu ceste, prioriteti izgradnje načrtovanih odsekov, itd. Vsi podatki opisujejo trenutno stanje, prav tako pa je podana tudi napoved za leto 2010. Banka podatkov evropskih avtocest je vzpostavljena na osebnem računalniku v okolju WINDOWS s programskim orodjem MS ACCESS. Podatki so razdeljeni glede na vsebino in shranjeni v različnih tabelah. Trenutno so v bazi podatki za prek 1700 avtocestnih odsekov, baza pa bo s priključevanjem novih območij še naraščala. Različnim uporabnikom so podatki na voljo v obliki različnih poročil, tabel, grafikonov in podobno. Na ta način uporabnik dobi ogromno natančnih podatkov o avtocestnih odsekih, ven­ dar si iz teh podatkov le s težavo ustvari pravo sliko stanja na omrežju. Na primer: na podlagi tabelaričnih podatkov si uporabnik le s težavo ustvari sliko prometnih tokov v neki državi. Z grafično predstavitvijo avtocestnih podatkov pridobimo tem podatkom novo uporabno vrednost. Za ta namen je bilo vzpostavljeno sodelovnaje med IRF in Prometno- tehniškim inštitutom (PTI) Fakultete za gradbeništvo in geodezijo v Ljubljani. PTI s svojimi večletnimi izkušnjami na področju geografskih informacijskih sistemov, še po­ sebno v prometu, je prevzel nadgranjo obstoječega si­ stema v sodoben prostorski informacijski sistem. BANKA AVTOCESTNIH PODATKOV IN GIS Cilji sistema Osnovni cilj nadgradnje Banke avtocestnih podatkov z GIS je omogočiti uporabo in razumevanje zbranih podatkov vsem ljudem, ki jih to zanima, in jim dati natančne, hitre in jasne odgovore na zastavljena vprašanja. Sistem ponuja boljši pregled tabelaričnih podatkov s pomočjo grafične predstavitve in uporabniku ponuja kartografski pogled vseh ali pa le izbranih podatkov. Poleg tega sistem v veliki meri pomaga pri odpravljanju napak, tako pri samih definicijah avtocestnih odsekov kot pri opisnih podatkih vezanih za te odseke. INTRODUCTION In the last years European Motorway Databank was established by the International Road Federation (IRF), Geneva, Switzerland. First database model was developed and principle of fixed motorway sec­ tions was accepted. With the help of local IRF or­ ganization in each country motorway network was divided into the sections where each got unique identification number which is the key for the whole database. For each road section beside the data, which exactly describe the motorway section loca­ tion, different data like status of construction, num­ ber of lanes, traffic volumes, traffic safety data, man­ agement and financing data, etc. for present (year 1994) and future (year 2010) situation were then collected. Motorway databank is implemented on personal computer in WINDOWS environment by the MS ACCESS software. Data are stored in different ta­ bles according to the subject. Already more than 1700 motorway sections is described in the data­ base and the database will grow with the time while new areas will be added. As the database output material for different users reports, tables, charts, etc. were produced mostly. In this way us­ ers can get exact data about the motorway system but because of the large amount of the data such a presentation is not so successful. For instance for user it is very hard to get impression of the traffic flows in some country only on the base of tabular data. With the graphical presentation of the motorway data the databank gets new value. For this reason the cooperation between the IRF and the Traffic Technical Institute, University of Ljubljana, Slovenia as the Geographic Information System specialist was established. MOTORWAY DATABANK AND GIS System goals The primary goal of the GIS extension of the Motorway Databank is to enable using and understanding of col­ lected motorway data to all interested people and to give quick, clear, accurate and easy to understand answers to all questions related to the motorway network. The system offers more powerful view of the tabular database through a graphical presentation and gives the users an overall or selective cartographic view of the data collected in the motorway databank. Beside this the system helps to man­ age consistency and correctness of the data collected. Implementacija sistema Za transformacijo IRF Banke avtocestnih podatkov v GIS moramo najprej vključiti prostorske informacije. Zato po­ trebujemo lego in potek avtocestnega omrežja v digitalni obliki, poleg tega pa moramo vsakemu odseku določiti enolični identifikator po specifikaciji obstojoče Banke avto­ cestnih podatkov. S pomočjo te enolične identifikacije lahko nato priključimo poljubne podatke iz obstoječe baze. Na podlagi naših izkušenj s podobnimi GIS projekti smo za osnovo izbrali ARC/INFO podatkovni format za prostor­ ske podatke in ARCVIEW za WINDOWS kot prezentacijsko orodje. ARCVIEW smo izbrali, ker ponuja vse in celo več, kot končni uporabniki zahtevajo in pričakujejo od sistema, program je uporabniku prijazen in enostaven za uporabo, poleg tega pa teče v istem okolju, kot je že realizirana obstoječa Banka avtocestnih podatkov (MS WINDOWS - MS ACCESS). Prav tako imamo znotraj paketa ARCVIEW neposredni dostop do baze v MS ACCESS skozi SQL povezavo in tako lahko zgradimo učinkovit sistem brez najmanjše spremembe v obstoječi bazi. Samo prostorska predstavitev avtocestnega omrežja nam ne da dovolj informacij, da bi si ustvarili pravo sliko o situaciji. Dodati moramo še nekaj informacij, ki rabijo kot pomoč pri orientaciji v prostoru. Za ta namen smo uporabili podatke iz publikacije Digital Chart of the World (DCW). V DCW so zbrani digitalni prostorski podatki za celoten svet v merilu 1:1000000 (1 :milijon), kar je praktično idealno za potrebe projekta, ki pokriva večje območje, kot je na primer Evropa. V naš sistem smo vključili naslednje sloje iz DCW: • • meje držav • območja večjih urbanih poselitev • teren (plastnice) System implementation To transform IRF Motorway Databank to an GIS first a spatial information must be added to the system. For this reason the motorway network must be prepared in digital format and section identificator associated with each mo­ torway section. After that the content of the Motorway Databank is linked to the motorway network through the unique motorway section identificators. On the base of our experience with GIS we select ARC/ INFO data format for spatial data and ARCVIEW 2.0 for WINDOWS as the presentation tool. We select ARCVIEW 2.0 because it offers all and even more what the end users expect from the system, it is easy to use and runs in the same environment as existing Motorway Databank (MS WINDOWS - MS ACCESS). Also from the ARCVIEW we have direct access to MS ACCESS database through the SQL connection and we can build powerful system with­ out any database transformation. Only spatial presentation of the motorway network does not give enough information to end user to get clear pic­ ture of the situation. We must add some background spa­ tial information and we use Digital Chart of the World (DCW) data for this purpose. The scale of the DCW data (1:1000000) is very appropriate for an overview project which cover all Europe. In the system we include the next layers from DCW: • country boundaries • boundaries of main urban areas • elevation levels • main rivers • main railway lines • main roads Spatial Information Tabular Data Digital Chart of the World Motorway Network IRF Motorway Database Slika 1: Komponente podatkovne baze geografskega informacijskega sistema Picture 1: Geographic information system database components • vode (morje, glavne reke in jezera) • glavne železniške linije • glavne ceste • večja pristanišča • pomembnejše energetske vode S tako kombinacijo programskega paketa ARCVIEW in DCW prostorskih podakov smo dobili učinkovito, vendar kljub temu poceni rešitev, ki nam omogoča prostorsko predstavitev Banke avtocestnih podatkov. Z implementacijo sistema lahko uporabnik izrisuje, ana­ lizira in poizveduje po podatkih v bazi. Nekateri standardni pogledi in izrisi so v sistemu že v naprej pripravljeni: • mreža avtocestnih odsekov z vozlišči (z imeni večjih lokacij v soseščini) • status izgrajenosti avtocestnih odsekov • prometni volumni (obstoječi/planirani) na teh odsekih (proporcionalni pogled) • vrsta obrabnega sloja • število voznih pasov • vrsta lastništva in vrsta pobiranja cestnine • main harbours • main utility lines With the combination of the ARCVIEW software and Dig­ ital Chart of the World data we get a nonexpensive solu­ tion to present IRF Motorway Databank graphically. With the implemented system users can display, query, analyse and plot the contents of the Motorway Databank. In the system some views and different layouts are pre­ pared in advance, like: • existing motorway sections and sections to be realised (differentiated by colour or typography according to re­ alisation status) • existing and future motorway nodes (with names of the most significant neighbouring localities) • traffic levels (present/future) on these sections (propor­ tional view) • nature of pavement on these sections (colour view). • number of lanes (present/future) on these sections (pro­ portional view) • nature of ownership and charging (present/future) on these sections (colour view). STOCKERAU IENNA) 41700! 73100 j 11200 4200 74500 23100 40500 KAPUV Sankt Johann MW - T ta fftc L ig h t Futufe / \ / 0 X / 1-10000 / \ / 10000-20000 A / 20000-30000 A / 30000-40000 A / 40000 - 50000 A / 50000 - 70000 70000 90000 A# 90000-120000 m m 120000 300000 Slika 2: Obstoječi volumen lahkega prometa za zahodni del Avstrije 2: Present light traffic volumes for the west part of Austria Produkti sistema Potencialni uporabniki sistema so predvsem vladne službe, transportne organizacije, svetovalne organizacije s pod­ ročja prometa, itd. Z Banko avtocestnih podatkov v GIS System Products Potential users of the system products are mostly govern­ ment offices, transportation organization, traffic consult­ ants firms, etc. With the GIS of Europe Motorway Databank lahko končnim uporabnikom ponudimo različne produkte. Najprej so to različne tabele v digitalnem formatu ali pa na papirju. Seveda je to možno že z obstoječim sistemom, brez GIS nadgradnje. Novi produkti so predvsem različni izrisi in pa celoten informacijski sistem kot celota za zahtevnejše uporabnike. Uporabniku lahko ponudimo raz­ lične izrise glede na: - vsebino za obstoječe in načrtovano stanje ( s t a n j e a v t o ­ c e s t n e m r e ž e , š t e v i l o v o z n ih p a s o v , v r s t a o b r a b n e g a s lo ja , p r o m e t n i v o lu m n i , i t d . ) - merilo in velikost izrisa - območje (E v r o p a , d e l E v r o p e , e n a d r ž a v a ) - informacije v ozadju (d r ž a v n e m e je , u r b a n a o b m o č ja , t e r e n , v o d e , c e s t e , ž e le z n i c e , i t d . ) - posebne zahteve uporabnika Uporabnikom, ki potrebujejo različne informacije bolj po­ gosto, lahko ponudimo tudi instalacijo kompletnega siste­ ma. Sistem vključuje: - IRF Banko avtocestnih podatkov (IRF) - digitalno avtocestno omrežje (PTI) - Digital Chart of the World (ESRI) - ARCVIEW (ESRI) - inštalacijo, šolanje in po potrebi dodatno izobraževanje (IRF, PTI) - vse spremembe v bazi (IRF, PTI) we can offer different products to the end users. The first are database tables in digital format or paper edition. Of course this can already be done without GIS capability with MS ACCESS. The new products are different plots and the complete system. With the system we can pro­ duce plots of different - content for present and future situations ( m o t o r w a y s t a ­ tu s , n u m b e r o f l a n e s , p a v e m e n t t y p e , t r a f f i c v o lu m e s , c h a r g i n g t y p e , o w n e r s h ip , e t c . ) - map scale and paper size - area ( E u r o p e , p a r t o f E u r o p e , s i n g l e c o u n t r y ) - background information ( s t a t e b o u n d a r i e s , u r b a n a r ­ e a s , e le v a t i o n d a t a , r o a d s , r a i lw a y s , r i v e r s , e t c . ) - special user request To the users which request different informations more frequently we can offer installation of the complete system composed of - IRF Motorway Databank (IRF) - digital motorway network (PTI) - Digital Chart of the World (ESRI) - ARCVIEW as presentation tool (ESRI) - training and education (IRF, PTI) - regular updates of the database (IRF, PTI) Slika 3: Potek avtocesnega omrežja glede na teren v Sloveniji Picture 3: Motorway network - terrain integration for Slovenia PILOTSKI PROJEKT GIS projekt smo pričeli ob koncu leta 1994, ko je bila dokončana prva izdaja Banke avtocestnih podatkov. Na področju Slovenije in Avstrije smo najprej izvedli pilotski projekt, ki predstavlja osnovo za testiranje GIS razširitve obstoječe baze. Avtocestno omrežje za Avstrijo in Slovenijo smo digitali­ zirali iz ustreznih topografskih kart. Segmentacija omrežja je bila izdelana v skladu s specifikacijo obstoječe Banke avtocestnih podatkov. Vse koordinate smo transformirali v tako imenovano “geografsko” projekcijo s fi-lambda vred­ nostmi. Na ta način smo omogočili, da uporabnik lahko kasneje s pomočjo paketa ARCVIEW sam izbere pro­ jekcijo, ki mu najbolj ustreza za posamezne poglede in izrise. Za potrebe predstavitve smo v paketu ARCVIEW vse tabele iz Banke avtocestnih podatkov povezali z atributivno tabelo avtocestnega omrežja. Za vsako tabelo smo kreirali eno več tem v odvisnosti od vrste podatkov v tabeli. Na ta način smo določene poglede lahko pripravili v naprej (klasifikacija, simboli, barve, itd.). Podatki iz DCW so bili naloženi in pripravljeni (knjižnice) s pomočjo programskega paketa ARC/INFO na delovni postaji (IBM 6000/250). Vzpostavili smo povezavo iz oseb­ nega računalnika, kjer smo poganjali ARCVIEW, do delov­ ne postaje in sistem je deloval brez problemov. Za končno realizacijo, ko bo sistem v celoti instaliran na osebnem računalniku, bo potrebno le podatke iz DCW prekopirati na osebni računalnik. Pilotski projekt je bil uspešno predstavljen na rednem srečanju IRF članov v maju 1995 v Glasgowu na Škot­ skem. Sistem sam in njegova učinkovitost ter prednosti v primerjavi z obstoječim sitemom so na udeležence sreča­ nja naredile velik vtis. Podprto je bilo nadaljevanje projekta in s tem razširitev na območje celotne Evrope. Tako smo predvideli, da bi projekt dokončali do konca leta 1995. ZAKLJUČEK GIS razširitev IRF Banke avtocestnih podatkov za Evropo predstavlja zelo učinkovito, hkrati pa enostavno in prijazno orodje za rokovanje z bazo podatkov. Prednosti GIS pred obstoječim sistemom so velike, kajti le GIS lahko ponudi kakovostno informacijo v primerni obliki kar največjemu številu ljudi. S kombinacijo programskega ARCVIEW in prostorske podatkovne baze Digital Chart of the World kot podatkov v ozadju smo dobili relativno poceni rešitev, ki omogoča realizacijo projekta v zelo kratkem času. PILOT PROJECT The GIS project started at the end of 1994 when first edition of Motorway Databank (MS ACCESS) was fini­ shed. In the first step the pilot project on 2 countries was implemented to provide a test basis for the GIS extension of the IRF Motorway Databank. The pilot project handles IRF motorway data for Austria and Slovenia. The motorway network for Austria and Slovenia was digi­ tised from topographic maps and segmentation was im­ plemented according to the IRF Motorway Databank speci­ fication. Coordinates were transform to fi-lambda values. In this way we can later in ARCVIEW select the projection for data presentation what is most appropriate for wide area projects. For presentation purpose for each Motorway Databank table copy of motorway network theme was done and the table was joined to the motorway network attributive table. In this way we can prepare some views of the data (classi­ fication, symbols, colors, etc.) in advance. Data form Digital Chart of the Word was loaded and pre­ pared (libraries) on workstation version of ARC/INFO (IBM 6000/250). After that the connection from PC ARCVIEW was established and the system operates through the network without any problem. For the final realisation of the product the DCW database was only copied from workstation to the PC. The pilot project was successfully presented at the regular IRF meeting in May 1995 in Glasgow, Scotland. The great impression was done with the system possibilities, effec­ tiveness and advantages of the presented products in comparison to existing products. The project got support by the IRF members and the next step in the project realisation was accepted. This should be the extension of the project on the whole Europe and it is planed to be realised until the end 1995. CONCLUSION The GIS extension of the IRF Europe Motorway Databank is very powerful and easy to use tool to manipulate motor­ way database. The advantages of the GIS in comparison to existing system are great and only GIS can offer good information in an appropriate form to the most of the interested people. With the combination of ARCVIEW 2.0 software and Digital Chart of the World database as a background data we get nonexpensive possibility to reali­ se project in very short time. PRESOJA VPLIVO V CESTE IN PROMETA NA OKOLJE TER IZBOR OPTIM ALNE VARIANTE POTEKA TRASE ENVIRONM ENTAL IMPACT ASSESSM ENT AND OPTIM AL UDK: 656.13:504.05 MARIJAN ZURA, PETER LIPAR* V tem članku predstavljava računalniško aplikacijo za izdelavo ocene vplivov ceste in cestnega prometa na okolje. Ocena ranljivosti okolja temelji na infor­ macijah o vegetaciji, živalskem svetu, vrsti tal, vod­ nih virih, klimatskih pogojih, naravni in kulturni dediščini, poselitvi itd. Ti podatki so shranjeni v t.i. vektorski ob lik i v posameznih informacijskih slojih podatkovne baze. Pri oceni ranljivosti moramo upo­ števati tudi relativno pomembnost posameznih poja­ vov. To pomembnost določim o z utežmi znotraj posameznega sloja in med sloji. Za izračun ran lji­ vosti moramo torej posamezne sloje topološko pre­ kriti. Za določitev optimalnega koridorja trase mo­ ramo združen sloj pretvoriti iz vektorske v rastrsko obliko. Ranljivosti lahko prikažemo grafično z raz­ ličn im i barvnimi odtenki in ta grafični prikaz lahko uporabimo kot eno od osnov za izdelavo različnih alternativ poteka trase. S prekrivanjem variant ter informacijskih slojev lahko analiziramo vplive vzdolž stacionaže. UVOD Presoja vplivov na okolje je postopek, v katerem iden­ tificiramo, opišemo in ocenimo neposredne in posredne vplive projekta na naslednje elemente: človek, živalstvo, In this paper we present ARC/INFO based applica­ tion for assessment of the road and traffic impacts to the environment. The estimation of the environ­ mental vulnerability is based on the information about fauna, flora, soil, water, air, climate, land­ scape, natural and cultural environment, urban ar­ eas, etc. and the importance of different phenom­ ena. The importance is established by weighting inside and between the layers. The vulnerability of individual layers as well of the jo in t layer can be presented in different colour shades and can be used as one of the graphics bases for the optimal room layout selection. Joint layer can be converted into the grid and the least impact corridor between origin and destination can be calculated. This corri­ dor can be used as another source of information for the optimal room layout selection. Several align­ ment alternatives can be overlaid above the jo in t environment layer and the cumulative impact can be assessed. Strip maps show the impacts on each alignment section. INTRODUCTION The Environmental Impact Assessment is a procedure, where we identify, describe and assess the direct and indirect effects of the project on the following factors: AVTORJA: • Doc. dr. Marijan Žura, dipl. gr. ing. Asist. mag. Peter Lipar, dipl. gr. ing. Ass. Prof. Marijan Žura, Ph. D. Ass. Peter Lipar, M. Sc. vegetacija, tla, vodni viri, zrak, klimatske razmere, naravna in kulturna dediščina itd. Nekatere vplive lahko merimo z znanimi postopki (npr. kmetijstvo, gozdarstvo, vodni viri, hrup, emisije, vibracije) ali pa določimo s simulacijskimi modeli, medtem ko drugih ne moremo določiti drugače, kot z ekspertno oceno. Pri izdelavi ekspertne ocene se moramo v največji možni meri izogniti subjektivnosti stro­ kovnjaka, zato moramo zagotoviti transparentnost po­ stopka in ažurne podatke. Pri zbiranju in analizi podatkov si lahko zelo pomagamo z orodji, ki nam jih nudi tehnologija geografskih informacijskih sistemov (GIS). METODOLOGIJA Postavitev problema Cilj presoje vplivov na okolje je poiskati koridor med dvema točkama, v katerem so vplivi projekta najmanjši. V tej začetni fazi definiramo študijsko območje in identificiramo sloje okolja, ki jih moramo upoštevati v analizi. Na podlagi izkušenj predlagamo, da študijsko območje zajema ob­ močje v oddaljenosti 400m od ravne črte med začetno in končno točko. Vnos podatkov o prostoru Po določitvi študijskega območja zberemo podatke o prostoru. Kot vedno predstavlja ta aktivnost najbolj ča­ sovno (in finančno) zahteven del projekta, vendar se situacija tudi na tem področju izboljšuje iz leta v leto. Trenutno je v Sloveniji na voljo že precej podatkov v digitalni obliki. Celotno območje države je pokrito s ske­ niranimi kartami od meril 1:250,000 do 1:5,000. Informacije so v precejšni meri ločene po slojih (topografija, izohipse, hidrografija, toponimi), kar olajšuje (pol)avtomatsko vekto- rizacijo. Veliko informacijskih slojev je bilo tudi že vek- toriziranih. Kot referenčno ozadje in dodatno informacijo pa lahko uporabljamo tudi digitalne ortofoto posnetke. Strokovnjaki za posamezna področja torej v tej fazi pri­ pravijo podatke o posameznih slojih. Po vnosu podatkov izdelajo oceno ranljivosti elementa okolja na posameznih lokacijah študijskega območja. Ponavadi uporabljamo štiri različne stopnje: 1 - ni vpliva 2 - majhen vpliv 3 - velik vpliv 4 - nedopustno Ranljivost posameznih lokacij lahko nato prikažemo gra­ fično v obliki različnih barvnih odtenkov. Model V naslednjem koraku združimo ^posamezne sloje v t.i. združen sloj elementov okolja. Studijsko območje torej predstavimo s poligoni z znanimi ranljivostmi posameznih elementov prostora. Skupno ranljivost pa izračunamo kot vsoto ocen pomnoženih z utežjo sloja. Uteži sloja so predstavljene v odstotkih. Npr. hidrografija predstavlja 40% skupne ranljivosti, medtem ko tla, kmetijstvo in gozdarstvo vsak po 20%. To pomeni, da so na tem območju vodni viri dvakrat pomembnejši kot kvaliteta zemljišča. Seveda je določitev teh razmerij med posameznimi sloji zelo težaven human beings, fauna, flora, soil, water, air, climate, land­ scape, material assets, cultural heritage and the inter­ action between the factors. Some impacts can be meas­ ured by known procedures (agriculture, forestry, water, noise, emissions, vibrations) because they have bounds determined by the legislation. Other impacts are evalu­ ated on the basis of simulation models while some are based only on expert’s perceptions. Here we must take into account the subjectivity of certain expertise. There­ fore it is necessary to assure the transparency of the procedure. While impact assessment is connected with extensive en­ vironment data collection and analysis, GIS technology represents the right tool for this task. METHODOLOGY Problem definition The goal of the Environmental Impact Assessment is to find the least impact corridor and to select the best align­ ment alternative between two places. In this early stage, analyst should define the study area and identify environ­ ment layers that should be considered in the analysis. Considering the previous experiences we suggest 400 m wide corridor around straight line between the origin and destination. Environment data input After we determine the study, we have to collect and enter information about the environment. As always this task represents the most time (and money) consuming part of the project. But in these days digital information in suit­ able format is more and more available also in Slovenia. The whole area of the country is covered by scanned images from scales 1:250,000 up to 1:5,000. The informa­ tion is separated into topography, contour lines, hidro- graphy layer and annotations what makes (semi)automatic vectorisation much easier. Several information layers have already been vectorised. Digital orthophoto can also be used as a background information. Different experts prepare the data bases on fauna, flora soil, water, climate, etc. When the data is entered, the estimation of area vulnerability is made, taking in consid­ eration available information on the particular phenomena in that area. The vulnerability of individual environmental factor, which is prepared on its own layer, is shown in different colour shades. Usually there are four different grades used for this esti­ mation: 1 - no impact 2 - small impact 3 - large impact 4 - unacceptable impact For example, grades from 1 to 4 are assigned to different soil types, according to the perception of the expert. Model After then, all these layers are joined into one layer which is later used in the analysis. Total vulnerability of each proces. Zahteva timsko delo, multi-disciplinaren pristop in verjetno tudi uporabo specialnih metod, ki so bile razvite za t.i. “mehke sisteme”. Optimalni koridor Model prostora, izdelan v predhodnem koraku, uporabimo za določitev optimalnega koridorja poteka trase med začetno in končno točko. Za ta namen pretvorimo združeni poligonski sloj iz vektorske v rastrsko obliko in z uporabo posebnih funkcij določimo območje, po katerem naj bi šle variante trase. To območje lahko uporabimo v naslednjem koraku izdelave variant ter se s tem že na samem začetku izognemo konfliktom z okoljem. polygon is calculated as a sum of grade multiplied by layer weight. Layer weights are represented as percents. For example, hydrology represents 40% of the total, while soils, agriculture and forestry 20% each. That means that water supplies are twice as much important as soils in this area. Of course, determination of this relative importance of each layer is very complicated task. It requires team work of different experts and probably application of some special methods developed for so called “soft systems”. Optimal corridor The optimal workflow would be first to determine the best corridor and after then to develop some possible layouts Slika 1: Optimalni koridor in variante trase Figure 1: Minimum impact corridor and alignment alterna­ tives Variante trase Za izdelavo variant trase lahko uporabimo specializirane programske pakete za projektiranje cest, kajti večina od njih omogoča izmenjavo podatkov z GIS paketi. V paket za projektiranje cest prenesemo podatke o terenu, zgrad­ bah, rekah itd. po obdelavi pa vrnemo v podatkovno bazo GIS geometrijo trase z vsemi ukopi in nasipi. Izbor optimalne variante through this corridor. The joint polygon layer is converted to grid and with use of costdistance and corridor functions one can develop the corridor where all the layouts should go through. This corridor can be plotted and used as a base map for design of road alignments thus designer can avoid major conflicts with environment already at the be­ ginning. Layouts Analizo nadaljujemo z določitvijo vplivov posameznih alternativ. Sloj, v katerem je shranjena geometrija posa­ meznih variant, prekrijemo z združenim slojem okolja. S tem določimo občutljivost okolja na posameznih odsekih Specialised roadway design packages can be used for alignment development. Most of them support data inter­ change with GIS packages. Digital terrain model, build­ ings, rivers, etc. can be imported to the design package, trase. Skupen vpliv variante določimo tako, da pomnožimo dolžino odseka z občutljivostjo prostora na tem odseku ter te zmnožke seštejemo. Rezultate lahko prikažemo v obliki tabel in histogramov s kumulativnim vplivom oz. vplivi vzdolž trase. Optimalna varianta je seveda tista, ki ima najmanjši kumulativni vpliv. and road alignments with all cut and fills exported to the GIS database. Selection of the best alternative When the different road alternatives are set, the estima­ tion can be done with overlaying the layers of area vulner­ ability and the road centrelines. In this way we can estab­ lish for each arc separate and total vulnerability of the underlying polygon. This vulnerability is multiplied by the length of the arc and cumulative value for each alternative is calculated. The results can be inspected as a tabular report and represented as a histogram. Stripmap of the vulnerability is also displayed. IZVEDBA Aplikacija je razvita s paketom Arclnfo 6.1.1 na delovnih postajah HP z operacijskim sistemom HP-UX. ZAKLJUČEK Predstavljena aplikacija omogoča izdelavo ocene vplivov ceste in cestnega prometa na okolje. Planerji in načrtovalci cest jo lahko uporabljajo za določitev optimalnega koridorja ter za izbor najboljše variante. Seveda pa moramo pro­ gram razumeti samo kot orodje za pomoč pri sprejemanju odločitev in ne kot odločujoč dejavnik. Omogoča nam hitro izvedbo analize z različnimi nabori uteži in s tem v pre­ cejšnji meri olajša najtežji del vrednotenja. Trenutno aplikacija še ne upošteva razlik v vplivih glede na oddaljenost od ceste, zato načrtujemo njeno dopolnitev. Poleg cone neposredne fizične spremembe (cestno telo) IMPLEMENTATION The application is implemented as a set of AMLs and MENUs with extensive use of ArcTools. It was developed and tested under Arclnfo 6.1.1 on HP-UX. CONCLUSIONS Presented application enables assessment of road and traffic impacts to the environment. Road planners and designers can use it for development of least impact corri­ dor and selection of the most suitable alignment alterna­ tive. The problem of ponders was touched and possible solution was suggested. When considered as if-then analy­ sis tool it can be of great help to decision makers. The application was tested on several projects in Slovenia and showed satisfactory results. As traffic impacts are not limited to the area of physical change (road body) the application should be enhanced bomo vrednotili tudi območje posrednega fizičnega vpliva (do 100m od ceste) in območje vizualnega stika (približno 450m od ceste). National Environmental Policy Act of 1969, USA Council Directive of 27 june 1985 on the assess­ ment of the effects o f certain public and private projects on the environment (85/337/EEC) O ffic ia l Journal of the European Communities No. L 175/49 The role of Environmental Impact Assessment in the Decisionmaking Process Merkblatt zur Umweltvertraeglichkeitsstudie in der Strassenplanung (MUVS), Entwurf, FGSV, Koeln 1990 Environmental Assessment - A Guide to the Proce­ dures, London HMSO, Department of the Environ­ ment, Welsh Office Glenwood Canyon 1-70, Environmental Concern, Colorado Department of Highways Transportation Facilities through D ifficu lt Terrain, Colorado Department o f Transportation Environmental Policy Statement, The Federal H igh­ way Administration Environmental Impact Statement, Guidelines and Format, Illinois Department of Transportation to take into account different zones of road environment impact: zone of direct physical modification (pavement), zone of direct modification (total land requirement-right of way), zone of indirect impact (area up to 100 meters from the road) and zone of visual contact (approximately 450 meters from the road). National Environmental Policy Act of 1969, USA Council Directive of 27 june 1985 on the assess­ ment of the effects of certain public and private projects on the environment (85/337/EEC) Official journal of the European Communities No. L 175/49 The role o f Environmental Impact Assessment in the Decisionmaking Process Merkblatt zur Umweltvertraeglichkeitsstudie in der Strassenplanung (MUVS), Entwurf, FGSV, Koeln 1990 Environmental Assessment - A Guide to the Proce­ dures, London HMSO, Department of the Environ­ ment, Welsh Office Glenwood Canyon 1-70, Environmental Concern, Colorado Department o f Highways Transportation Facilities through D ifficu lt Terrain, Colorado Department of Transportation Environmental Policy Statement, The Federal High­ way Administration Environmental Impact Statement, Guidelines and Format, Illinois Department o f Transportation ACKNOWLEDGMENTS The authors would like to thank Eugene W. Cleckley, Chief of Environmental Operations Division US DOT, FHA and Hermann Guenther, P.E. Director of Civil Engineering - Daniel, Mann, Johnson & Mendenhall for their sugges­ tions and information sources. OPTIČNO VODENJE OSI IN GEOM ETRIJSKO OBLIKOVANJE CEST O ptica l leading of ax is and geom etrica l form ing of roads UDK: 625.711.3.04 PETER LIPAR* P O V Z E T E K Perspektivna slika, ki jo vidi voznik, je lahko precej drugačna od tridimmenzionalne predstave projek­ tanta. Za estetsko spojitev ceste in krajine je zelo pomembno hkratno horizontalno in vertikalno vo­ denje cestne osi. V tem prispevku skušamo pred­ staviti različne nepravilnosti pri projektiranju in podati možne rešitve. Tridimenzionalni prikaz je narejen s pomočjo računalniške grafike. UVOD Potek ceste v prostoru definiramo z geometrijskimi ele­ menti v tlorisnem in višinskem poteku trase. Zavedati se moramo, da vidi voznik samo perspektivno sliko ceste, ki pa je lahko drugačna od tiste, ki si jo je zamislil projektant. Zaradi tega moramo že v začetnih fazah projekta preverjati tridimenzionalno vodenje trase. Pri projektiranju ceste in pri njeni spojitvi s krajino so pomembni funkcionalni in oblikovno estetski kriteriji: • funkcionalni kriteriji so posledica vozno - dinamičnih analiz • oblikovno - estetski kriteriji se postavijo na podlagi vizualnih predstav in doživljanja ceste z gledišča njiho­ vega uporabnika - voznika in potnika; estetski kriterij je zelo pomemben zaradi “človeškega dejavnika” , ki vpliva na varnost prometa The perspective image of road can differ from the tridimensional that the designer had in mind. For the fusion o f the road and landscape it is important simultaneous horizontal and vertical leading of the laying out. In this paper I try to show some mistakes in road design and some solutions. A ll 3D pictures are made w ith particular software. INTRODUCTION The line of a road in the space is defined by geometrical elements in the ground-plan and height flow of the laying out. One has to be aware that the driver sees only the perspective image of the road which can differ from the one that the design engineer had in mind. For this reason the three-dimensional leading of the laying out has to be checked already in the first stages of the project. When designing a road and at its fusion with the land­ scape, functional as well as formative-aesthetic criteria are important: • functional criteria are a consequence of the driving- dynamic analyses • the formative-aesthetic criteria are set on the basis of visual concepts and ideas of the road from the side of its user - driver and passenger; the aesthetic criterion is of AVTOR: Asist. mag. Peter Lipar, dipl, gr. ing. ' Ass. Peter Lipar, M, Sc. Drugi vidik je zaznavanje ceste iz okolice. Izpolnjevanje funkcionalnih ter oblikovno - estetskih kriterijev je potrebni pogoj za spojitev ceste in krajine, ni pa tudi zadosten. Za to je potrebno izpolniti tudi dodatne pogoje. Hkrati je pa razumljivo, da samo estetski kriteriji še ne zagotavljajo tudi ustreznih prometno tehničnih rešitev. Projektant mora upoštevati vse kriterije - da je cesta varna in da se spaja s krajino. Za optimalno rešitev je potrebno angažiranje prometne psihologije, teorije informacij, raču­ nalniške perspektivne slike, krajinske arhitekture in teh­ nične kibernetike. OPTIČNO VODENJE OSI CESTE Za dobro optično vodenje trase so potrebni naslednji pogoji: • prostorska slika ceste mora delovati “umirjeno” • cesta mora imeti pregleden potek na večji dolžini • potek ceste mora biti pravočasno in nedvoumno ra­ zumljivo dojet. Geometrijsko oblikovanje Smoter geometrijskega oblikovanja je skladnost sestav­ ljanja projektnih elementov, tako da prostorska slika ceste učinkuje ugodno in pozitivno na vedenje voznika in mu vliva občutek varnosti. Za to ni dovolj, da so vsi izbrani horizontalni in vertikalni elementi trase v mejah dopustnih vrednosti, ki so odvisne od računske hitrosti, ampak je potrebno vzpostaviti širšo medsebojno odvisnost projektnih parametrov. Tu gre za prostorsko predstavo, ki jo formirajo vodilne (strukturne) linije ceste - rob ceste, črte, odbojne ograje, ki so v vidnem polju voznika. Vtis zaporedja teh elementov je za voznika lahko popolnoma drugačen od predstave o cesti, ki jo dobimo iz projektne dokumentacije V okviru dojemljive preglednosti na 25 do 30 sekundah, vožnje kar znaša pri hitrosti 120 km/h okoli 1000m, lahko oko voznika zazna več geometrijskih oblik - premo, krožni lok, prehodnico in vertikalne zaokrožitve. Dolžina vidnega polja je enaka približno štiri kratni razdalji hitrosti izražene v metrih. To pomeni, da so te vrednosti pri večjih hitrostih višje, le širina vidnega polja je manjša. Najpogostejše napake in priporočila: A Prema Dolge preme učinkujejo monotono in utrujajoče na voz­ nika. Težko je pravilno oceniti njeno dolžino. Zato naj bo prem čimmanj, njihove dolžine pa naj bi bile odvisne od računske hitrosti na predvideni cesti in naj ne bi presegale razdalje 20 x Vr, kar ustreza največji globini vidnega polja. B Krožni lok Krožni lok ima boljše oblikovne kakovosti kot prema. Mini­ malna dolžina loka mora biti takšna, da voznik dojame stopnjo zakrivljenosti. To praktično pomeni 2 - 5 sekund vožnje. Maksimalna dolžina pa je omejena z vizuro dojem­ ljive preglednosti. a great importance because of the “human factor” which influences the traffic safety Another view is perceiving the road from the surrounding. Meeting the functional and formative-aesthetic criteria are necessary in order to achieve the fusion of the road and the landscape. But this does not suffice, some other addi­ tional conditions are to be met, too. At the same time it is understandable that only aesthetic criteria do not provide adequate traffic-technical solutions. The design engineer has to consider all the criteria - that the road is safe and that it is fused with the landscape. For an optimal solution the traffic psychology, theory of information, computer perspective images, landscape ar­ chitecture and technical cybernetics are to be engaged. OPTICAL LEADING OF THE ROAD AXIS For a good optical leading of the laying out the following conditions are to be met: • the space image of the road has to have a “soothing” effect • the road has to have an easily surveyable line in a larger length • the road line has to be perceivable duly and undoubt­ edly. Geometrical design The purpose of the geometrical design is conformity of putting together the project elements through which the space image of the road will have a pleasing and positive effect on the behaviour of the driver and will give them a sense of safety. It is not enough, though, that all the chosen horizontal and vertical elements of the laying out are within the allowable values which depend on the computational speed, but also a wider interdependence of the project parameters has to be established. This is a matter of spatial image which is formed by the leading (structural) lines of the road - road border, lines, safety rails which are in the visual field of the driver. For the driver the impression of a sequence of these elements can be completely different from the image of the road that is obtained from the project documentation. Within the perceivable surveyability at each 25 to 30 sec­ onds of the driving, which amounts at the speed of 120 km/h to about 1000 m, the eye of the driver can sense several geometrical forms - straight, circular bend, cross­ ings and vertical round-ups. This means that these values are higher at higher speed, only the width of the visual field is smaller. Most common errors and recommendations: A Straight Long straight have a monotonous and tiresome effect on the driver. It is difficult to assess its length correctly. For this reason there should be as few straight as possible C Prehodnica Prehodnica daje najboljše optične učinke. Glede pravilne dolžine prehodnice obstaja več teorij. Najboljše oblikovne rešitve se dosegajo pri dolžinah,ki so približno enake dolžinam lokov in pri velikosti parametra R/3