砂土中桩基动力响应振动台模型试验  

Shaking Table Model Test of Dynamic Response of Pile Foundation in Sand

作　　者：胡枫 宋春雨[1] 时昆鹏 李得睿 陈龙珠[1] HU Feng;SONG Chunyu;SHI Kunpeng;LI Derui;CHEN Longzhu(School of Naval Architecture,Ocean&Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学船舶海洋与建筑工程学院,上海200240

出　　处：《实验室研究与探索》2023年第1期79-84,共6页Research and Exploration In Laboratory

基　　金：国家自然科学基金项目(51678361)。

摘　　要：针对近海工程中桩基受到的风、波浪等水平动力荷载,利用自制的振动台加载系统提供水平简谐荷载,在砂土中开展了单桩和群桩动力模型试验,研究荷载幅值及荷载频率对桩基动力响应的影响。运用数字图形相关形变测试系统监测桩基位移,验证了加载装置的有效性,并对桩周土体的变形进行了动态监测。试验发现,桩身弯矩最大值随荷载幅值增大而增长。1、3、5 Hz 3种加载频率对桩身弯矩分布影响很小,桩身弯矩主要分布在土体表面以下11倍桩径深度范围内,最大弯矩出现在约4倍桩径深度处。群桩前排桩的弯矩大于后排桩。试验结果可为桩基在水平动力荷载下的动力响应研究提供参考,该试验系统能为类似的桩基动力模型试验提供技术保障。In order to study the horizontal dynamic loads on pile foundation in offshore engineering,such as wind and wave,dynamic model tests are carried out.Using the self-developed shaking table loading system to provide horizontal harmonic load,model tests of single pile and pile group are carried out in sand to study the effects of load amplitude and load frequency on dynamic response of pile foundation.The digital image correlation deformation testing system is used to monitor the displacement of pile foundation,which verifies the effectiveness of the loading device and dynamically monitors the deformation of the soil around the pile.It is found that the maximum value of pile bending moment increases with the increase of displacement load.The three loading frequencies of 1 Hz,3 Hz and 5 Hz have little effect on the distribution of pile bending moment.The pile bending moment is mainly distributed in the depth of 11 times the pile diameter below the soil surface,and the maximum bending moment appears in the depth of about 4 times the pile diameter.The bending moment of the front pile of pile group is greater than that of the rear pile.The results can provide theoretical reference for the study of dynamic response of pile foundation under horizontal dynamic load,and the test system can provide technical support for similar pile foundation dynamic model tests.

关 键 词：桩基础 砂土 振动台 水平简谐荷载 数字图形相关 动力模型试验 

分 类 号：TU473[建筑科学—结构工程]