考虑土—结构相互作用下隔震桥梁的随机响应分析  

Study on Random Response of Isolated Bridge Considering Soil-structure Interaction

作　　者：刘鹏飞[1] 金波[1] 

机构地区：[1]同济大学航空航天与力学学院,上海200092

出　　处：《力学季刊》2010年第3期376-381,共6页Chinese Quarterly of Mechanics

摘　　要：研究了考虑土—结构相互作用下隔震桥梁的随机地震动响应。应用子结构方法将桥梁结构分成上部和下部两个子结构。地基土看作是各向同性的弹性半空间,土对结构的作用简化成水平和转动方向的刚度和阻尼元件。地震动用平稳随机过程模拟,应用虚拟激励法求解结构的随机响应。分析表明,土—结构相互作用对隔震桥梁有一定的影响,但相对非隔震桥梁来说影响较小;即使在地基土较软弱的情况下,隔震措施一直有效的发挥作用,可以说隔震措施对不同的地基土都有一定的适应性或鲁棒性。但是隔震支座在地基情况较差时,位移响应较大,因此在软弱地基应用隔震应特别注意,防止发生碰撞及落梁。This paper studies on random response of bridge considering the interaction between soil-structure. Substructure method is applied to divide the bridge into superstructure and substructure. Foundation soil is treated as isotropic elastic half-space . The effect of soil to structure is simplified into the element of stiffness and damping, which is in horizontal and rotated directions. Stationary random process is adopted to simulate the ground motion. Pseudo- excitation method is used to solve the stochastic response. Analysis showed that the soil-structure interaction influences on the isolated bridge, but more impact on non-isolated bridge. Even in the weak soil conditions, isolation measures have been effective. So isolation measures to the different soil conditions have adaptability or robustness. However, the response of isolation bearing＇s displacement is large, especially in poor soil condition; therefore, special attention should be paid to prevent a collision and falling down of main girders.

关 键 词：土-结构相互作用 隔震桥梁 虚拟激励法 随机响应 

分 类 号：TU435[建筑科学—岩土工程] U442[建筑科学—土工工程]