【摘要】 根据隔震连续桥梁的设计特点,利用2个正交的非线性水平弹簧单元来模拟铅芯橡胶支座的双向非线性特性,基于大型有限元软件,合理选取了强震记录作为地震输入,建立了加设隔震支座的港珠澳大桥有限元模型,并进行了强地震动作用下的地震响应分析。分析结果表明:采用减隔震支座后,桥梁结构通过延长自身的自振周期避开了地震的卓越周期;同时依靠减隔震支座的滞回耗能,有效地减少了输入到桥梁结构中的地震能量,降低了桥梁结构的地震响应,使大部分构件处于弹性工作阶段,从而达到保护主体结构的目的。更多还原

【Abstract】 According to the design features of seismically isolated continuous bridges,the bi-directional nonlinear characteristics of lead rubber bearing are simulated by using two orthogonal nonlinear level spring elements.Based on the finite element software,the analysis models of seismically isolated and non-isolated continuous bridges are established.And the nonlinear seismic response for these analysis models is carried out under the function of the reasonably chosen seismic motion.The analytic results indicate that the natural period of seismically isolated bridge can be prolonged to avoid the principal period of ground,and the seismic energy of structure can be efficiently consumed by the hysteretic energy dissipation of lead rubber bearing.So the response of bridge structure can be reduced to make sure that the most of component work in the elastic phase,and the structure can be well protected.更多还原