地震荷载作用下土体变形试验研究  

Experimental studies on soil deformation under seismic loads

作　　者：孟凡超[1,2] 袁晓铭 MENG Fanchao;YUAN Xiaoming(Institute of Disaster Prevention,Sanhe 065201,China;Hebei Key Laboratory of Earthquake Disaster Prevention and Risk Assessment,Sanhe 065201,China;Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150080,China;Key Laboratory of Earthquake Disaster Mitigation,Ministry of Emergency Management,Harbin 150080,China)

机构地区：[1]防灾科技学院,河北三河065201 [2]河北省地震灾害防御与风险评价重点实验室,河北三河065201 [3]中国地震局工程力学研究所地震工程与工程振动重点实验室,黑龙江哈尔滨150080 [4]地震灾害防治应急管理部重点实验室,黑龙江哈尔滨150080

出　　处：《地震工程与工程振动》2024年第3期157-163,共7页Earthquake Engineering and Engineering Dynamics

基　　金：地震科技星火计划项目(XH204402)。

摘　　要：为研究不规则地震荷载对土体变形特性的影响,对砂土试样开展了系统的动三轴试验。试验中分别对3种不同密度砂土试样施加了4条具有不同峰值的不规则地震应力时程及其循环次数为20周的等幅正弦荷载,以便开展对比研究。结果表明:在地震荷载及其等幅循环荷载输入下,砂土试样的应变增长曲线差异显著,荷载类型及荷载波形是影响土单元应变时程发展特征的主要因素。考虑荷载不规则性得到的修正系数受荷载类型和砂土相对密实度的影响,不受输入荷载动应力幅值大小及砂土类型的影响。最后针对地震荷载下土单元变形的计算,给出了以常规的等幅三轴变形试验为依据的估算方法。In order to study the effect of irregular seismic loads on soil deformation characteristics,systematic dynamic triaxial tests were carried out on sand samples in this study.In the test,four irregular seismic stress time histories with different peak values and constant amplitude cyclic sinusoidal loads with 20 cycles were applied to three sand samples with different densities for comparative study.The results show that the strain growth curves of sand samples are significantly different under the input of seismic loads and constant amplitude cyclic loads,and the load type and load waveform are the main factors affecting the strain time history development characteristics of soil elements.The correction coefficient obtained by considering the load irregularity is affected by the load type and the relative compactness of sand,and is not affected by the magnitude of the dynamic stress amplitude of the input loads and the type of sand.Finally,for the calculation of soil element deformation under seismic loads,an estimation method based on conventional constant amplitude triaxial deformation test is given.

关 键 词：地震荷载 变形特性 等幅往返荷载 修正系数 估算方法 

分 类 号：P315.9[天文地球—地震学] TU43[天文地球—固体地球物理学]