2045 KB46 KB199920252016Cai, LigangHong, YiShi, WeiminYang, ChengZhao, Yongshengletnik:62številka:nr. 11str. 665-677ISSN:0039-2480COBISSID_HOST:15037467URN:URN:NBN:SI:doc-UMI7D53UenZveza strojnih inženirjev in tehnikov Slovenije etc.Strojniški vestnikdušenjekontaktna togostneenakomerna porazdelitev pritiskaobdelovalni strojiteorija fraktalnega kontaktavijačne zvezeStiffness and damping model of bolted joints with uneven surface contact pressure distribution|Bolted connections are widely employed to fix the structural components, in which the bolted joint is one of the weakest parts and can significantly affect the dynamic characteristics of the machine tool. In this research, a stiffness and damping model based on the uneven surface contact pressure is presented for the bolted joint to accurately predict the dynamic characteristic of a bolted assembly. The normal and tangential stiffness and damping of the contact surface can be deduced based on the fractal contact theory. However, the contact surface pressure of bolted joint is unevenly distributed due to the influence of the concentrated force of multi-bolts. Therefore, the pressure of the contact surface is introduced to define the stiffness and damping of bolted joint. The assumption is that the contact surface is flat in the macro-scale. Then, we can obtain the pressure distribution of contact surface through the finite element (FE) method. The nonlinear relationship of stiffness, the damping of the bolted joint, and the pressure of contact surface can be obtained and assigned to the FE model based on the pressure distribution of the contact surface. An experimental set-up with a box-shaped specimen is designed for validating the proposed model. The equal pre-tightening force and bending moment effect case studies are provided to demonstrate the effectiveness of the model. The results show that the proposed model can be used to accurately predict the dynamic characteristic of the machine toolVijačne zveze se množično uporabljajo pri konstrukcijskih komponentah, kjer so pogosto eden najšibkejših členov in lahko pomembno vplivajo na dinamične lastnosti obdelovalnega stroja. V tej raziskavi je bil ustvarjen model togosti in blaženja s porazdelitvijo kontaktnega pritiska po neenakomerni površini, ki točno napoveduje dinamične lastnosti sestava. Normalno togost, tangencialno togost in dušenje kontaktne površine je mogoče izpeljati na podlagi teorije fraktalnega kontakta, ki je običajno enak za vse elemente togosti in dušenja po celotni kontaktni površini. Ta hipoteza pa ni primerna za vijačne zveze zaradi vpliva koncentracije sil pri sestavih z več vijaki. Zaradi neenakomerne porazdelitve pritiska se togost in dušenje spreminjata po kontaktni površini vijačne zvezeTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za strojništvo