粗颗粒含量对粗颗粒土抗剪强度指标的影响研究  

Study on the Influence of Coarse Particle Content on Shear Strength Index of Coarse-grained Soils

作　　者：马捷[1] 韩文喜[1,2] 李宝成 梁春晓 MA Jie;HAN Wenxi;LI Baocheng;LIANG Chunxiao(College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China;State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学环境与土木工程学院,四川成都610059 [2]成都理工大学地质灾害防治与地质环境保护国家重点试验室,四川成都610059

出　　处：《人民珠江》2019年第12期25-30,共6页Pearl River

基　　金：国家重点基础研究发展“973”计划项目“机场高填方长期变形规律及优化设计方法研究”(2014CB047003)

摘　　要：抗剪强度指标作为粗颗粒土工程特性中较为关键的一项,其值与粗颗粒土的级配紧密相关。选取灰岩质碎石土填料进行击实和大型三轴试验,研究了粗颗粒土抗剪强度指标随P5含量(粒径大于5 mm颗粒含量)的变化规律。试验表明:当P5含量在35%~85%范围内时,粗颗粒土的最大干密度和内摩擦角都随着P5的增加先增加后减少,且都在P5为75%时达到峰值;粗颗粒土的黏聚力随着P5含量先减小后增大,且当P5为55%时达到最小值;粗颗粒土的最优含水率随着P5含量先增大后减小,且当P5为55%时达到最大值;P5含量在75%时级配良好且拥有较好的抗剪性能。The shear strength index is one of the key engineering properties of coarse-grained soil,and it is closely related to the gradation of coarse-grained soil.This paper studies the variation laws of the shear strength index of coarse-grained soil with the P5(which refers to particles with size greater than 5 mm)content by using the limestone gravel soil filler for compaction and large-scale triaxial test.The test shows that when the P5 content is between 35% and 85%,1)the maximum dry density and internal friction angle of the coarse-grained soil increase first and then decrease with the increase of P5 content,and reach the peak value when P5 content is 75%;2)the cohesion of coarse-grained soil decreases first and then increases with the increase of P5 content,and reaches the minimum value when P5 content is 55%;3)the optimum moisture content of coarse-grained soil increases first and then decreases with the increase of P5 content,and reaches the maximum value when P5 content is 55%.In conclusion,the coarse-grained soil is featured with good gradation and shear performance when the P5 content is 75%.

关 键 词：粗颗粒土 P5含量 黏聚力 内摩擦角 

分 类 号：TU470[建筑科学—结构工程]