基于颗粒流的膨胀土裂隙填充细观试验研究  

Mesoscopic Experimental Study on Crack Filling of Expansive Soil Based on Particle Flow

作　　者：王少鹏 张文慧[1,2] 张福海[1,2] 白岩辉 陈宇 WANG Shaopeng;ZHANG Wenhui;ZHANG Fuhai;BAI Yanhui;CHEN Yu(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;Research Institute of Geotechnical Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,南京210098 [2]河海大学江苏省岩土工程技术工程研究中心,南京210098

出　　处：《河南科学》2021年第6期978-985,共8页Henan Science

基　　金：国家自然科学基金资助项目(51778211);江苏省自然科学基金资助项目(BK20171434)。

摘　　要：为了更好地研究蒙脱石裂隙填充对膨胀土影响的作用机理,先进行室内试验,之后通过颗粒流法对直剪试验进行模拟,分析颗粒在剪切过程中的细观规律.在填充层厚度为1、1.5、2 mm三种情况下,通过位移等值线图和转角云图等从具体数值上分析颗粒运动的变化规律.主要结论如下:颗粒的位移随着剪切的进行不断增大,1 mm填充层位移变化随剪切的进行变化最为均匀,1.5 mm和2 mm填充层位移变化规律较为接近;当填充层厚度不同时,剪切面附近颗粒转角大小的变化规律相似,但在上部和下部有明显差别;颗粒的平均转角在剪切面附近达到最大值,沿中间位置向上部和下部逐渐减小;颗粒力链的变化规律符合宏观下力学规律,在剪应力峰值处强力链的方向基本一致.In order to better study the mechanism of the effect of montmorillonite crack filling on expansive soil,the laboratory test was carried out first,and then the direct shear test was simulated by particle flow method to analyze the mesoscopic law of particles in the shear process.In the condition when the filling layer thicknesses are 1,1.5 and 2 mm,the variation law of particle motion was analyzed by displacement contour map and rotation angle cloud map.The main conclusions are as follows.The displacement of particles increases with the shear,and the displacement of 1.5 mm and 2 mm is the most uniform,and the displacement of 1.5 mm and 2 mm is close to each other.When the thickness of filling layer is different,the change law of the rotation angle of particles near the shear plane is similar,but there is obvious difference between the upper part and the lower part.The average rotation angle of particles reaches the maximum value near the shear plane,and gradually decreases along the middle position to the upper and lower parts.The change law of the force chain of the particles conforms to the macroscopic mechanical law,and the direction of the strength chain at the peak of the shear stress is basically the same.

关 键 词：颗粒流 裂隙填充 细观规律 直剪试验 

分 类 号：TU443[建筑科学—岩土工程]