限位装置对桩基础高墩摇摆反应的影响

Restrainer Effect on Rocking Response of Tall Pier with Pile Foundations

摘要:

提出了限位装置的模拟方法，完善了桩基础高墩摇摆隔震的分析模型.基于某铁路高墩桥梁，输入3条强震记录，采用非线性时程分析方法进行了限位装置的影响分析.讨论了限位装置初始间隙及屈服力的变化对墩顶位移与墩底弯矩的影响规律.结果表明，限位装置减小墩顶位移的同时会增大墩底弯矩，墩顶位移受限位装置初始间隙的影响较大，墩底弯矩受限位装置初始间隙的影响较小，桩基础高墩的摇摆反应受限位装置屈服力的影响较大.

关键词:高墩; 桩基础; 摇摆隔震; 限位装置

Abstract:

Modeling method of the restrainers was proposed for the seismic analysis of the tall pier pile foundations rocking isolated system. Effect of the restrainer on the rocking response of a railway tall pier was investigated through nonlinear time history analysis by inputting three strong ground motions. The displacement at the top and the moment at the bottom of the pier are discussed as functions of the initial gap and yielding force of the restrainer. The results show that the restrainer decreases the displacement at pier top, while it increases the base moment. The initial gap of restrainer has greater effect on the top displacement than the base moment. It is also observed that the yield force of restrainer affects the rocking response of the tall pier pile foundations isolated system significantly.

Key words:tall pier; pile foundations; rocking isolation; restrainer