The effect of seismic action on stability of saline soil subgrade in cold region based on isothermal stratification method

作     者：Jie Cheng Yu Zhang Ying Ma Xuerui Chen Ning An Jie Cheng;Yu Zhang;Ying Ma;Xuerui Chen;Ning An

作者机构：School of Traffic and TransportationLanzhou Jiaotong UniversityLanzhou730070China Key Laboratory of Railway Industry of Plateau Railway Transportation Intelligent Management and ControlLanzhou Jiaotong UniversityLanzhou730070China Gansu Institute of Engineering GeologyLanzhou730030China 

出 版 物：《Earthquake Research Advances》 (地震研究进展（英文）)

年 卷 期：2024年第4卷第3期

页      面：66-81页

核心收录：

学科分类：081401[工学-岩土工程] 08[工学] 0814[工学-土木工程] 

基　　金：supported by a grant from the Gansu Provincial Department of Natural Resources Science and Technology Innovation Talent Cultivation Project (2022-09) the geological disaster prevention projects of Gansu Provincial Bureau of Geology and Mineral Resources(2022-09) Natural Science Foundation of Gansu province(No.22JR5RA326) 

主　　题：Subgrade stability Saline soils Acceleration amplification effect Seismic design 

摘      要：With the change of seasons, the shear strength of saline soil subgrade filler will change with the change of external temperature, which will aggravate the adverse effects of seismic on the subgrade. To explore the influence of seismic action on the stability of saline soil subgrade under the influence of temperature on the strength of saline soil subgrade filler, this paper first carried out saline soil shear tests at different temperatures to obtain the influence of temperature on the shear strength of saline soil. Then, the temperature field of the saline soil subgrade was simulated, and then based on the subgrade isothermal stratification model and FLAC3D, the displacement and acceleration amplification effects of seismic action on the shady slope, sunny slope and subgrade of saline soil subgrade in different months were analyzed. The following conclusions were finally drawn: under the action of seismic, In the process of the change of subgrade temperature of Qarhan-Golmud Expressway between 7.7°C and 27°C, the change of saline soil cohesion is the main factor affecting the stability of subgrade slope, and the maximum and minimum values of subgrade surface settlement appear in September and June of each year,respectively. In August, the differences of settlement between the shady slope and the sunny slope shoulder of the subgrade were the largest, and the acceleration of the shady slope and the sunny slope and the inside of the subgrade changed most significantly in the vertical direction. Special attention should be paid to the seismic early warning in the above key months;In the range from both sides of the shoulder to the centerline of the roadbed,the acceleration amplification effect starts to increase significantly from about 3m from the centerline of the roadbed to the centerline, so it is necessary to pay attention to the seismic design of this range.