2469 KB32 KB199920252013Jovanović, MiomirRadoičić, Goranštevilka:4letnik:59str. 260-268, SI 46ISSN:0039-2480COBISSID:12840987URN:URN:NBN:SI:doc-R7EEIVZ3enAssociation of Mechanical Engineers and Technicians of Slovenia et al.Zveza strojnih inženirjev in tehnikov Slovenije et al.Strojniški vestnikdinamični odgovorkoeficient dušenjalarge amplitudepalična konstrukcijastolpni žerjavistructural dampingstrukturno dušenjetower cranetransient responsetruss structurevelika amplitudaExperimental identification of overall structural damping of system|The dynamic behaviour of large and complex structures largely depends on damping resistance in the structure. A portion of the structural energy is lost to deformations in material, friction between the contact surfaces, and relative motion within the structure. Often, in an analysis of numerical models, before the dynamic analysis of transient events (transient analysis), the damping resistance is adopted on the basis of recommendations, which implies an error of transient response (introduced by frequencies, logarithmic decrements and maximal amplitudes). Decreasing amortized vibratory movement is dependent on the extent of the structural damping. This paper presents the importance of structural damping in structural analysis and shows the experimental and theoretical procedure for identifying G values of the structural damping coefficient. A model for determining the G coefficient is shown in the example of a real tower crane structure. The experimentally obtained values were then used in the transient numerical FEM analysis, as the basis for adopting the conclusions about the dynamic behaviour of this class of structures (transportation machines). The effect of the external perturbation force of trapezoidal impulse form (lifting and quickly lowering of load) is introduced and the dynamic task, as an example of the use of the G coefficient G, is solved. The experimentally determined damping (theoretically isolated for tall truss structures) can be used in similar transient analysesTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za strojništvo