不同连接形式桩筏系统动力响应数值模拟  

Numerical simulation of dynamic response of pile raft system with different connection types

作　　者：任迪凡 杜娟[1] 王在成 雷枭鹏 Ren Difan;Du Juan;Wang Zaicheng;Lei Xiaopeng(School of Civil and Architectural Engineering,Hainan University,Haikou 570228,China)

机构地区：[1]海南大学土木建筑工程学院,海南海口570228

出　　处：《海南大学学报（自然科学版）》2023年第4期422-428,共7页Natural Science Journal of Hainan University

基　　金：国家自然科学基金(52268056);海南省重点研发计划项目(ZDYF2022SHFZ277);海南省自然科学基金(520RC548)。

摘　　要：针对不同连接形式对桩筏系统抗震性能的影响,开展了3种连接形式桩筏系统在循环荷载作用下的数值模拟研究.通过对桩土动接触压力峰值曲线、土层顶部和筏板顶部加速度反应谱等动力响应的对比分析,探寻垫块和褥垫层对桩筏系统抗震性能的影响规律.结果表明:桩顶设置褥垫层可以最有效地调动地基土潜力,桩身弯矩峰值降低4kN·m,筏板顶加速度峰值降低7%,桩顶加速度峰值降低9%;桩顶埋设垫块桩身弯矩峰值降低6 kN·m,设置垫块可使筏板加速度峰值降低45%,桩顶加速度峰值降低35%,可以有效调动地基土潜力,对土层顶部和筏板顶部加速度放大效应减少最有利.2种连接形式均可减小上部结构加速度响应,减震效果良好.In the report,aimed at the effects of the different connection forms on the seismic performance of pile raft system,the numerical simulation of three connection forms of pile raft system under cyclic load was carried out.Through the comparative analysis of the peak curve of pile-soil dynamic contact pressure,acceleration re-sponse spectrum of the top of soil layer and the top of raft,the effects of cushion block and cushion layer on the seismic performance of pile raft system was explored.The results showed that the cushion layer on the pile top can most effectively mobilize the potential of the foundation soil.The peak moment of the pile shaft decreases by 4 kN·m,the peak acceleration of the raft top decreases by 7%,and the peak acceleration of the pile top decreas-es by 9%;The peak bending moment of the pile shaft embedded with cushion blocks at the pile top decreases by 6 kN·m.Setting cushion blocks can reduce the peak acceleration of the raft by 45%and peak acceleration of the pile top by 35%,which can effectively mobilize the potential of the foundation soil,which is most beneficial to reduce the acceleration amplification effect at the top of the soil layer and the top of the raft.The acceleration re-sponse of the upper structure can be reduced by the two connection forms,and the damping effects is good.

关 键 词：桩筏系统 数值模拟 桩土相互作用 桩身弯矩 筏板顶加速度 

分 类 号：TU473.11[建筑科学—结构工程]