Dynamic centrifuge tests for influence of vertical inertia force of overburden soil on earthquake damage response of shallow-buried underground frame structures#br#
Xu Chengshun1 Li Yang1,2 Du Xiuli1 Li Zheng1 Zhou Yanguo3
1. Key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education, Beijing University of Technology, Beijing 100124, China;
2. China Academy of Railway Sciences Co., Ltd., Beijing 100081, China;
3. Key Laboratory of Soft Soils and Geoenviromental Engineering, Zhejiang University, Hangzhou 310058, China
Abstract:Previous researches have showed that the columns under different axial compression ratios performed different lateral deformation capacities, which is the key factor of aseismic performance of the shallow-buried subway frame structures. In this study, dynamic centrifuge model tests on earthquake damage to underground structure are carried out. The model tests aim to shed lights on the effect of the increased axial compression ratio of column, which is induced by the vertical earthquake excitation, on earthquake damage responses of shallow-buried underground frame structures. To simulate the effect of vertical inertia force of overburden soil, the steel grits are mixed into the overburden soil layer. Test results indicate that the way of mixing the steel grits into the overburden soil layer has little influence on dynamic characteristics of soil-structure system and relative horizontal displacement between ceiling slab and bottom slab due to seismic excitation. The increased vertical inertia force of overburden soil significantly changes the contact pressure distribution between underground structure and surrounding soil, and the stress states of structural member are changed accordingly, leading to the increase of axial compression ratio of the key vertical load bearing column in the underground frame structure. Consequently, increasing vertical inertia force of overburden soil effectively increases the stresses of the structural frame and axial compression ratio of middle columns, so that the underground frame structure is more susceptible to seismic damage.
许成顺 李 洋 杜修力 李 政 周燕国. 上覆土竖向惯性力对浅埋地下框架结构地震损伤#br#
反应影响离心机振动台模型试验研究[J]. 土木工程学报, 2019, 52(3): 100-110,119.
Xu Chengshun Li Yang Du Xiuli Li Zheng Zhou Yanguo. Dynamic centrifuge tests for influence of vertical inertia force of overburden soil on earthquake damage response of shallow-buried underground frame structures#br#. 土木工程学报, 2019, 52(3): 100-110,119.