承台几何参数对高桩承台地震动水效应的影响  

The influence of the geometric parameters of the cap on the hydrodynamic effect for the elevated pile cap foundation

作　　者：游科华[1] 魏凯[1] 袁万城[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《地震工程与工程振动》2013年第4期189-194,共6页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(51278376;90915011);同济大学土木工程学院光华基金项目

摘　　要：传统方法在计算承台动水效应时无法全面考虑承台复杂几何参数的影响,这往往会造成计算结果与实际情况之间的差异。本文采用基于势流体理论的数值模拟方法,建立了考虑结构-水相互作用承台动力特性分析模型,通过对矩形承台及带复杂倒角的承台大量的参数分析,研究了承台振动频率、倒角、几何尺寸,及入水深度对承台地震动水附加质量的影响。研究发现:承台自振频率会影响承台的附加质量,但其影响较小;承台长宽比或厚度的增加都会增大承台的附加质量;同时,承台倒角形式和大小对承台附加质量有明显影响,忽略倒角的影响,将放大承台的动水效应;承台入水深度的增加会引起承台动水附加质量的增大,但深度超过一定范围后,附加质量基本保持稳定。The traditional method for calculating the cap hydrodynamic effect could not consider the complicated ge- ometries, which makes the differenices between the calculation results and the actual situation. The dynamic analy- sis model of cap considering structure-water interaction is built up using numerical method based on potential-based fluid theory. Then, the influences of geometries of the rectangular cap and cap with complicated chamfers on the hydrodynamic added mass are studied respectively, which include the cap vibration frequency, the geometrical size, the chamfer and the immersing depth of the cap. The following conclusions are drawn ： （ 1 ） the vibration fre- quency has little effect on the hydrodynamic added mass ; （ 2 ） the increase of the ratio of length to width and the thickness of the cap will increase the added mass ; （ 3 ） both form and size of chamfers have significant effects on the hydrodynamic added mass, and ignoring chamfer will amplify this effect; （4） the added mass will increase with the increase of the immersing depth of the cap, but keep constant if the depth exceeds a certain value.

关 键 词：深水桥梁 高桩承台基础 势流体理论 动水附加质量 承台 

分 类 号：TU311.3[建筑科学—结构工程] P315.91[天文地球—地震学]