Evolution of cracks in the shear bands of granite residual soil  

作　　者：Chengsheng Li Lingwei Kong Ran An 

机构地区：[1]Department of Civil and Environmental Engineering,Shantou University,Shantou,515063,China [2]State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,430071,China [3]College of Urban Construction,Wuhan University of Science and Technology,Wuhan,430065,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2022年第6期1956-1966,共11页岩石力学与岩土工程学报（英文版）

基　　金：the Building Fund for the Academic Innovation Team of Shantou University,China(Grant No.NTF21017);the Special Fund for Science and Technology of Guangdong Province in 2021(Grant No.STKJ2021181);the National Natural Science Foundation of China(Grant No.11672320)。

摘　　要：The evolution of shear bands and cracks plays an important role in landslides.However,there is no systematic method for classification of the cracks,which can be used to analyze the evolution of cracks in shear bands.In this study,X-ray computed tomography(CT)is used to observe the behavior of granite residual soil during a triaxial shear process.Based on the digital volume correlation(DVC)method,a crack classification method is established according to the connectivity characteristics of cracks before and after loading.Cracks are then divided into six classes:obsolete,brand-new,isolated,split,combined,and compound.With evolution of the shear bands,a large number of brand-new cracks accelerate the damages of materials at the mesoscale,resulting in a sharp decrease in strength.The volume of brandnew cracks increases rapidly with increasing axial strain,and their volume is greater than 50%when the strain reaches 12%,while the volume of compound cracks decreases from 54%to 21%.As cracks are the weakest areas in a material,brand-new cracks accelerate the development of shear bands.Finally,the coupling effect of shear bands and cracks destroys the soil strength.

关 键 词：Shear band Crack classification method Digital volume correlation(DVC) X-ray computed tomography(CT) Granite residual soil 

分 类 号：TU45[建筑科学—岩土工程]