地震作用下简支梁桥梁间碰撞的反应性能

现行<铁路桥涵技术规范>和<铁路工程抗震设计规范>均没有考虑地震作用下简支梁桥发生的碰撞问题,通过对一座两跨16 m简支梁桥的分析可以知道,在简支梁桥一般所采用的梁间距下,有可能发生梁间的碰撞作用,碰撞作用会改变原有桥梁的受力形式,加大了其破坏程度.针对梁间距、地震波、地基土的变形等影响梁碰撞的不同因素做了分析讨论.结果表明梁间距较小时产生的碰撞响应也较小,足够大的梁间距使相邻梁不发生碰撞作用,输入不同地震波,考虑地基的转动变形都会对碰撞产生不同的影响.

Characteristic of Pounding Response of the Simple-Supported Bridges during Earthquake

Pounding effects of adjacent superstructure segments in simple_supported bridge during earthquake is not considered in the Railway Bridge_culvert Skill Code and the Railway Engineering Seismic Design Code. In this paper, the bridge analyzed is a two_span simple_supported bridge with 16 m span length. The effect of earthquake_induced pounding can be found between the adjacent segments on the applied separation gap. Pounding increases the structural damage because it changes the forces acting on bridge. The factors of affected the bridge pounding were taken into consideration such that the gap size, earthquake excitations, the rotation deformation of foundation. It is found that the smallest response can be obtained for very small gap sizes and gap sizes large enough to prevent pounding, and that earthquake excitations also influence the pounding of adjacent segments considering the foundation conditions.