石灰岩碎石土大型直剪试验研究  

Large-scale Direct Shear Test Research on Limestone Gravel Soil

作　　者：魏东旭 彭雄志[2] 张佳 范帅 冯瑨 Wei Dongxu;Pleng Xiongzhi;Zhang Jia;Fan Shuai;Feng Jin(Shandong Transportation Planning&Design Institute Group Co.,Ltd.;Southwest Jiaotong University;Jinan Huanghe Road and Bridge Construction Group Co.,Ltd.)

机构地区：[1]山东交通规划设计院集团有限公司,济南市250031 [2]西南交通大学,成都市610031 [3]济南黄河路桥建设集团有限公司,济南市250031

出　　处：《勘察科学技术》2024年第4期1-5,43,共6页Site Investigation Science and Technology

摘　　要：该文以云南昭通碎石土为研究对象,现场取样并在室内配制五组不同含石量的碎石土重制样,开展室内大型直剪试验和数值计算分析,研究不同含石量对石灰岩碎石土抗剪强度的影响规律。试验结果表明:石灰岩碎石土的抗剪强度随着含石量的增加而增大;内摩擦角φ试验值为25°~45°,黏聚力c试验值为20~37 kPa。其中内摩擦角φ在含石量0~20%之间增幅较大,当含石量大于20%后有所增长,黏聚力c出现“假黏聚力”。数值分析表明剪切带主要分布在剪切缝位置。Taking the Zhaotong limestone gravel soil in Yunnan as the research object,this study involves sampling on-site and preparing five groups of remolded gravel soil samples with different stone contents in the laboratory.Large-scale direct shear tests and numerical analysis are conducted to investigate the effect of difrerent stone content on the shear strength of limestone gravel soil.The test results show that the shear strength of limestone crushed soil increases with the increase of stone content,the test value of internal friction angle is φ25°-45°,and the test value of cohesion c is between 20-37 kPa.Among them,the internal friction angle φ increases greatly when the stone content is between 0-20%.When the stone content is greater than 20%,it increases,and the cohesion c appears"apparent cohesion".Numerical analysis shows that shear bands are mainly distributed at the position of shear joints.

关 键 词：石灰岩碎石土 含石量 室内大型直剪试验 抗剪强度 剪胀性 

分 类 号：TU41[建筑科学—岩土工程]