Abstract:
For continuous girder bridges, once the restrainer is installed at the movable pier, the seismic analysis model would be characterized by the friction nonlinearity at the movable support and conctact-and-collision nonlinearity of the restrainer. Based on the characteristics of the friction element and the contact element, finite contact-and-friction element models are presented, with the contact element being elastic and elasto-plastic, respectively. The hysteresis curve for the contact-and-friction element is given and the stiffness under unloading is derived according to various curves. The contact-and-friction element models were applied to the nonlinear time-history analysis of continuous girder bridges which contain friction-type movable supports and restrainers. The seismic dissipating effect of the restrainers on the seismic responses of the fixed pier is analyzed and it is shown that the contact-and-friction element can be used in the detailed aseismic model of continuous girder bridges which contain both restrainers and movable supports.