Post-liquefaction shearing behaviour of saturated gravelly soils: Experimental study and discrete element simulation

作     者：Yong Wang Yanli Wang Lingwei Kong Zhiliang Sun Yong Wang;Yanli Wang;Lingwei Kong;Zhiliang Sun

作者机构：State Key Laboratory of Geomechanics and Geotechnical EngineeringInstitute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Yangtze River Scientific Research InstituteKey Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water ResourcesWuhan430010China 

出 版 物：《Journal of Rock Mechanics and Geotechnical Engineering》 (岩石力学与岩土工程学报（英文版）)

年 卷 期：2020年第12卷第5期

页      面：1119-1130页

核心收录：

学科分类：08[工学] 081401[工学-岩土工程] 0818[工学-地质资源与地质工程] 0815[工学-水利工程] 0813[工学-建筑学] 0814[工学-土木工程] 

基　　金：financially supported by the National Natural Science Foundation of China(Grant Nos.51979269 51779017 and 41702348)。 

主　　题：Post-liquefaction Micro-mechanism Gravelly soil Deformation Discrete element method(DEM) 

摘      要：To investigate the post-liquefaction shearing behaviour of saturated gravelly soil,laboratory tests were conducted using a staticedynamic multi-purpose triaxial apparatus.In addition,numerical simulations using the discrete element method(DEM)were performed to preliminarily understand the micromechanism of gravelly soil in monotonic loading after liquefaction.The influences of dry density,initial confining stress and degree of liquefaction on the post-liquefaction shearing behaviour of gravelly soil were discussed,and the evolution of the micro-parameters of the granular system was also analysed.The results show that the stressestrain responses of gravelly soil after liquefaction can be divided into three stages:(1)low strength stage,(2)super-linear strength recovery stage,and(3)sublinear strength recovery stage,which are distinctly different from those of the general saturated gravelly soil without previous cyclic loading.The initial state and prior dynamic stress history have significant influences on the post-liquefaction shearing behaviour of gravelly soil.The DEM simulation revealed that the average coordination number sharply increases,the contact normal shows an obvious orientation distribution,and the destroyed force chain backbones are reconstructed in the monotonic reloading process after liquefaction.The evolution of the micro-parameters of the granular system clearly reflects the interior interaction process and micro-mechanisms in the particles during the three different stages of the macro-mechanical behaviour of gravelly soil.