考虑竖向地震作用的高桥墩P-Δ效应分析  

P-Δ Effect of High Bridge Pier Considering Vertical Earthquake Action

作　　者：吴泽玉[1] 张清晓[2] 

机构地区：[1]郑州大学,河南郑州450001 [2]华北水利水电学院,河南郑州450045

出　　处：《工程抗震与加固改造》2012年第3期40-43,共4页Earthquake Resistant Engineering and Retrofitting

基　　金：国家自然科学基金资助项目(50978232)

摘　　要：由50年设计基准期的水平地震系数推导出4类桥梁水平地震系数,按一般规律,可求出不同类型桥梁相应的竖向地震系数。选择满足几何边界条件和力学边界条件的变形曲线,用能量方法推导出具有通用性的变形公式,进而可求出墩顶位移与墩底弯矩。与不计P-Δ效应的计算结果相比,考虑P-Δ效应的位移与弯矩都在很大程度上得到放大,特别是在罕遇地震作用下,效果更加明显。对于高柔性桥墩,尚需要考虑高振型和材料非线性的影响。The lateral earthquake coefficient of four type bridges can be calculated by means of the lateral earthquake factor of 50 years design reference period, then according to common rule, the vertical earthquake coefficient can be found. Utilizing the curve meeting the mechanical and geometrical boundary, the general deformed shape is derived using the energy method, therefore, the maximum displacement of the upper pier and moment of bottom pier can be acquired. Comparing with the displacement and moment getting by different load case, the value of ignoring the P-Δ effect is the minimum, especially with rare strong earthquake. As for high flexible pier, the high mode effect and material nonlinearity also should be taken into account.

关 键 词：高桥墩 能量法 P-Δ效应 设计基准期 罕遇地震 

分 类 号：U441.3[建筑科学—桥梁与隧道工程] U443.22[交通运输工程—道路与铁道工程]