为了解决隔震桥梁的梁体和支座位移在近断层地震激励下易超出容许值的问题，提出了基于混合罚函数理论的隔震支座参数优化方法。以四跨铅芯橡胶支座（LRB）隔震高架连续梁桥为背景，制作了该背景的1：10缩尺模型桥，开展了模型桥振动台台阵试验。基于混合罚函数理论编制了用于优化 LRB 屈服力、初始刚度和硬化比的 MATLAB 程序，并分别对优化前后的模型桥在单条或多条地震激励下的响应进行了仿真和试验分析。结果表明：模型桥在优化前后的响应仿真值与试验值非常接近；多条地震激励下的目标函数值要比单条地震激励下的略大一些；优化后的模型桥在单条和多条地震激励下的梁体和支座位移均在容许值内，且各墩底内力均未明显增大。%To solve the problem of girder displacement and bearing displacement of the seismic-isolated bridge tend-ing to be beyond their allowable values due to the near-fault ground motions,the seismic-isolated bearing parame-ters optimization method based on the mixed penalty function theory was proposed in this paper. Taking the four-span elevated continuous girder seismic-isolated bridge with the lead rubber bearing(LRB)as the background,the 1 / 10 scale model of this background was made,and then the shaking table array test of the model bridge was car-ried out. The MATLAB program was developed by using the mixed penalty function theory,which is used to opti-mize the LRB yield force,initial stiffness and hardening ratio,and then the seismic responses of the model bridge before and after optimization due to single-earthquake excitation and multi-earthquake excitation were obtained by simulation and test analysis,respectively. The results show that the simulation values of the seismic responses of the model bridge before and after optimization are very close to the testing values. The objective function value due to multi-earthquake excitation is slightly larger than the objective function value due to single-earthquake excitation. The optimized model bridge structural girder displacement and bearing displacement responses are all within allowed values,and the internal forces of all the pier bottoms do not increase obviously.
展开▼
