侧限条件下路基压实黏土的水平残余应力试验分析  

Experimental analysis of horizontal residual stress of compacted subgrade clay under confined conditions

作　　者：刘宏扬 罗强[1,2] 周鑫 吴鹏[1,2] 李傲赢 LIU Hong-yang;LUO Qiang;ZHOU Xin;WU Peng;LI Ao-ying(School of Civil Engineering Southwest Jiaotong University,Chengdu 610031,China;MOE Key Laboratory of High speed Railway Engineering Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]高速铁路线路工程教育部重点实验室,四川成都610031

出　　处：《实验力学》2020年第3期441-450,共10页Journal of Experimental Mechanics

基　　金：国家基础研究发展规划项目(973计划)(2013CB036204);国家自然科学基金项目(51878560)。

摘　　要：路基填土是一种松散的土体材料,经压实才能体现出良好的力学性质。路基填土被压实后,土体中会产生较大的水平残余应力。掌握路基压实黏土水平残余应力的主要特征是进一步研究路基结构工程性质的关键。为此,本文研制了一套在侧限条件下测试压实黏土水平残余应力的试验装置,进行了高液限黏土在不同压实度和含水率条件下的水平残余应力变化规律试验分析。试验表明:在相同含水率条件下,压实黏土水平残余应力随压实度的提高呈折线形增大;在同一压实度下,压实黏土的水平残余应力随含水率的升高近似呈线性减小趋势;对比分析可知,压实度对压实黏土水平残余应力的影响程度明显大于含水率。Subgrade fill is a kind of loose soil material that can reflect good mechanical properties by compaction.After the subgrade fill is compacted,the horizontal residual stress can be dramatically enhanced in the soil.Mastering the main characteristics of horizontal residual stress of compacted subgrade clay is the key to further studying the engineering properties of subgrade structure.In this work,a device for testing the horizontal residual stress of compacted subgrade clay under confined conditions is developed.The experimental analysis of the horizontal residual stress of high liquid limit clay under different degrees of compaction and moisture content conditions is carried out.The results show that under the same moisture content,the residual stress of compacted subgrade clay increases with a piecewise linear trend as the compaction degree increases.Under the same compaction degree,the horizontal residual stress of compacted subgrade clay decreases nearly linearly with the increase of moisture content.The comparison among them shows that the compaction degree has greater influence than the moisture content on the horizontal residual stress of compacted subgrade clay.This work provides the understanding of the engineering characteristics of compacted subgrade soil.

关 键 词：路基压实黏土 水平残余应力 侧限条件 压实度 含水率 

分 类 号：TU411.93[建筑科学—岩土工程]