以一座城市立交匝道桥为工程背景,利用MIDAS/CIVIL建立该曲线钢箱梁桥的三维有限元模型,考虑不同的地震波输入方向,分析高阻尼隔震橡胶支座的减震效果,并探讨支座参数变化对曲线钢箱梁桥地震效应的影响。计算结果表明,地震荷载作用下,采用参数合理的高阻尼橡胶支座能减小曲线钢箱梁墩底剪力达27%~69%。支座屈服力、屈服前后刚度比值和初始水平刚度增大时,支座水平方向位移的有变小的趋势,但并不显著。支座参数的改变可以显著调节所在桥墩内力,对其余桥墩内力的影响较小,在设计过程中应根据受力要求合理调整各墩支座参数。
Based on an overpass ramp bridge, this paper establishes a 3D finite element model of this curved steel box-girder bridge with high damping rubber bearing. Considering the orientation of earth- quake wave, the effect of using high damping rubber bearings was analyzed and the influences of bearing parameters on damping effects are discussed. The results show that the application of high damping rubber bearings can reduce the shear forces at the bottom of piers up to 27% - 69%. The displacement of bearings decreased as the yield force, the stiffness ratio before and after yield and the initial horizontal stiffness enlarged, but not dramatically. The parameters of bearing can affect the internal force of the pier which the bearing located and have little influence to others piers. The parameters of bearing should be adjusted according to the force requirements of the structure during design.