倾斜场地非均匀土-桩-结构地震相互作用振动台试验与数值分析  

Shaking table test and numerical analysis of non-uniform soil-pile-structure seismic interaction in inclined ground

作　　者：张卢明 周勇 王志佳[2] 于丰泽 闫孔明 ZHANG Luming;ZHOU Yong;WANG Zhijia;YU Fengze;YAN Kongming(Nuclear Industry Southwest Survey&Design Institute Co.,Ltd,Chengdu 610061,China;School of Civil Engineering and Architecture,Hainan University,Haikou 570228,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]核工业西南勘察设计研究院有限公司,四川成都610061 [2]海南大学土木建筑工程学院,海南海口570228 [3]西南交通大学土木工程学院,四川成都610031

出　　处：《地震工程与工程振动》2020年第5期224-236,共13页Earthquake Engineering and Engineering Dynamics

基　　金：国防科工局科研项目(科工二司[2015]548号);国防基础科研计划(咨国防[2017]1790号)。

摘　　要：为了研究地震作用下倾斜场地桩-土-结构的相互作用规律,以西南山区某固体废物处置场为例,采用分离相似设计方法和基于连续介质力学的离散元法,进行了群桩结构模型振动台试验与数值分析。通过输入不同幅值的地震波,探讨了整个体系动力响应、处置场单元位移、桩身动应力变化规律及处置场的整体稳定性。并得出如下结果:(1)岩土体是否饱和对模型结构体系的地震动力响应和体系内力影响较大,饱水后位移和内力均要大于饱水前,但体系最大位移在安全范围内;(2)体系的加速度放大效应主要产生在桩身部分,上部结构整体运动主要以平动为主;(3)桩身轴力沿桩深度呈先增大后减小的趋势,增至强风化带底部最大,整个桩身以受压为主;桩身剪力最大值发生在嵌固段下端,强风化带以上剪力幅值及变化均较小,饱水后桩身剪力自上而下逐渐增大;弯矩自桩顶以下呈先增大后减小,然后再反向增大的趋势,最大弯矩发生在2/3桩身周围;(4)处置场整体稳定,但1号~2号处置场桩基设计应加强,处置场下部斜坡应进行抗滑桩等措施进行加固;(5)本项研究可为倾斜场地非均匀土-桩基-结构体系设计计算提供参考。In order to study the interaction law of pile-soil-structure in inclined site under earthquake,a solid waste disposal site in southwest mountain area was taken as an example.Shaking table test and numerical analysis of pile group structure model were carried out by using separation similarity design method and discrete element method based on continuum mechanics.The dynamic response and pile body dynamic response of the whole system were discussed by inputting seismic waves of different amplitudes.The dynamic response of the whole system,the unit displacement of the disposal site,the dynamic stress change rule of the pile body and the overall stability of the disposal site are discussed.Research conclusions:(1)the saturation of rock and soil has a great influence on the seismic response and internal force of the model structure system,and the displacement and internal force after saturation are greater than those before saturation,but the maximum displacement of the system is within the safe range;(2)the acceleration amplification effect of the system mainly occurs in the pile body,and the overall movement of the superstructure is mainly translational motion;(3)the axial force of the pile body presents along the pile depth.The maximum shear force occurs at the lower end of the embedded section,and the shear amplitude and variation above the strong weathering zone are small,and the shear force increases gradually from top to bottom after water saturation;the bending moment increases first below the top of the pile,then decreases,and then increases in reverse direction,and the maximum bending moment occurs in 2/3 of the piles.Around the disposal site;(4)The disposal site is stable as a whole,but the pile foundation design of No.1~2 disposal site should be strengthened,and anti-sliding piles should be taken to reinforce the lower slope of the disposal site.(5)This study can provide reference for design and calculation of non-uniform soil-pile-structure system in inclined site.

关 键 词：倾斜场地 地震 分离相似设计方法 群桩-土-结构相互作用 振动台试验 数值分析 

分 类 号：TU473.1[建筑科学—结构工程]