Microscopic Study on the Influence of Moisture Content on the Shear Failure Behavior of Unsaturated Soil
The moisture content is an important factor determining the shear strength of unsaturated soil.The indoor direct shear tests and PFC3D simulations were used to study the evolution mechanism of direct shear failure in unsaturated soil with a certain moisture content(16％～24％).The experimental results show that when other conditions such as normal stress remain unchanged,the shear strength and cohesion of unsaturated soil gradually decrease with the increase of water content;Under the same conditions,the number of particles rolling and sliding in the layer area increases with the increase of moisture content.When the moisture content of unsaturated soil reaches 24％,the shear band width is between(17～19)d50,which is 1.63 times that of unsaturated soil with 16％moisture content;The moisture content has a significant impact on the ratio of the number of bond failures in unsaturated soil to the total bond content,and this effect is synchronous with the for-mation and evolution of shear bands.This study can better reproduce the microscopic failure characteristics in macroscopic direct shear tests and provide reference basis for geotechnical simulation.
unsaturated soilmoisture contentdiscrete element methoddirect shear testmicro-scopic mechanism
万方数据
维普
