考虑水平-竖向地震作用效应的地下结构离心机振动台试验方法适用性研究  

Study on applicability of centrifuge shaking table test method for underground structure subjected to horizontal-vertical seismic effects

作　　者：闫冠宇 许成顺[1] 张梓鸿 杜修力[1] YAN Guanyu;XU Chengshun;ZHANG Zihong;DU Xiuli(Key Laboratory of Urban Security and Disaster Engineering,Ministry of Education,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124

出　　处：《建筑结构学报》2023年第11期15-25,共11页Journal of Building Structures

基　　金：国家自然科学基金面上项目(52078020)。

摘　　要：竖向地震作用对地下结构地震破坏响应的影响至关重要。由于受使用的离心机振动台功能限制和现有模型箱的功能局限,直接模拟多向地震作用下的场地响应存在较大困难,因此基于已完成的采用结构顶部掺入一定比例钢砂来等效模拟竖向地震作用引起的竖向惯性力影响,并考虑水平-竖向地震作用的地下结构离心机振动台试验,建立土-结构动力相互作用的有限元模型,验证数值模型的正确性;同时,采用已验证的数值模型,进一步探究上覆钢砂模拟竖向地震动作用引起的竖向惯性力影响的等效试验方法的适用性。研究结果表明:竖向地震作用和结构上部掺入钢砂均对土-结构体系水平向地震响应的影响并不显著;与仅水平地震作用相比,水平-竖向地震作用增大了结构中柱、侧墙的总应变和轴力的峰值响应;与水平-竖向地震作用(竖向地震动与水平地震动同时达到加速度峰值)相比,在水平地震作用下,虽然结构上部掺入钢砂的等效试验方法增大了结构中柱及侧墙的轴力和总应变的初始值,但中柱、侧墙的总应变幅值、轴力、剪力、弯矩等内力水平与水平-竖向地震作用时基本接近,结构上部掺入钢砂的方法可以有效反映竖向承力构件在竖向地震动作用下的总应变和内力的峰值响应。与水平-竖向地震作用(竖向地震动先于水平地震动达到加速度峰值)相比,在水平地震作用下,结构顶部掺入钢砂的方式可能会高估结构构件的总应变峰值响应,但仍能反映结构竖向承力构件在竖向地震动峰值时刻的内力与总应变水平。Vertical seismic action has an important effect on the seismic failure response of underground structures.Due to the functional limitations of the existing centrifuge shaking table and the existing model box,it is difficult to directly simulate the site response under multi-directional seismic action.Therefore,based on a completed centrifuge shaking table test of underground structure with the top of the structure mixed with a certain proportion of steel sand to equivalently simulate the effect of vertical inertia force caused by vertical seismic action,and considering the horizontal-vertical seismic action,a finite element model of soil-structure dynamic interaction was established,and the correctness of the numerical model was verified.At the same time,the applicability of equivalent test method for simulating vertical inertia force induced by vertical ground motion of overburden steel sand was explored based on the verified numerical model.The results show that the horizontal seismic response of soil-structure system is not significantly affected by vertical seismic action and the addition of steel sand to the upper part of the structure.Compared with considering only horizontal seismic action,the horizontal-vertical seismic action increases the peak response of the total strain and axial force of the column and the side wall.Compared with the horizontal-vertical seismic action,in which the vertical and horizontal ground motions reach their peak at the same time,under horizontal seismic action,although the equivalent test method of adding steel sand to the upper part of the structure increases the initial values of axial force and total strain of the central column and side wall of the structure.However,the peak responses of total strain,axial force,shear force,bending moment and other internal forces of the central column and side wall with steel sand are basically close to those considering the horizontal-vertical seismic action.The method of adding steel sand to the upper part of the structure can effective

关 键 词：地下结构 离心机振动台试验方法 竖向地震作用 数值模拟 等效试验方法 

分 类 号：TU433[建筑科学—岩土工程]