【摘要】 地震荷载作用下的桩基动力反应在工程设计中越来越受到重视。基于桩-土-结构整体动力有限元法,结合工程实例,建立有限元分析模型,设置粘弹性人工边界,研究水平地震荷载作用下地基土层特性变化对桩基抗震反应的影响。着重探讨了上软下硬和上硬下软两种土层分布情况下,软硬土层相对厚度及弹模比变化对桩基抗震反应的影响。结果显示:桩基和筏基交接处桩顶截面和软硬土层分界处的桩身截面均可能是内力最大截面,桩顶截面和软硬土分界处桩身截面都应是设计需考虑的控制性截面,地基土层特性变化对于桩基弯矩的影响较剪力的影响显著。更多还原

【Abstract】 The seismic responses of foundation piles have invoked more and more attention in design.With the finite element method of complete dynamic interaction of pile-soil-structure combined with a typical case study in engineering,a finite element analysis model was created with a visco-elastic boundary set at the artificially truncated boundary to study the effects of soil characteristics on seismic responses of foun- dation piles for the case of horizontal seismic loads.In two cases of top soft and bottom hard and of top hard and bottom soft of the soil profile,seismic responses of foundation piles were studied through the variation of relative thickness and the ratio of elastic moduli of the soil layers.The result shows that cross- sections of the pile at the intersection of pile-rafter foundation and at the interface of soft and hard soil lay- ers might be the sections of maximum internal forces so that these sections of the pile should be considered as the control sections in the design of the pile body.Effects of characteristics of the soil profile on the mo- ment of piles are more significant than those on the shear.更多还原