不同因素影响下层间错动带颗粒破碎和剪切强度特性试验研究  

Particle crushing and shear behaviour of an infilled joint soil under different conditions

作　　者：赵阳[1,2] 周辉[1] 冯夏庭[1] 邵建富[1,3] 江权[1] 闵弘[1] 江亚丽[4] 黄可[4] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点试验室,武汉430071 [2]华北水利水电学院资源与环境学院,郑州450011 [3]法国里尔科技大学里尔力学试验室,法国里尔59655 [4]中国水电顾问集团华东勘测设计研究院,杭州310014

出　　处：《岩土力学》2013年第1期13-22,共10页Rock and Soil Mechanics

基　　金：国家重点基础研究发展计划(973)项目(No.2010CB732006);国家自然科学基金(No.50979104);中国科学院知识创新工程重要方向项目(No.KZCX2-EW-QN115)

摘　　要：为了获得不同初始颗粒粒径分布和含水率对层间错动带颗粒破碎和剪切强度特性的影响,通过对比泥夹碎屑、泥夹粉砂、全泥型3种不同层间错动带类型与现场3种不同含水率(10%、7%和3%)试样在法向压力2～10 MPa作用下的反复直剪试验和剪切面颗粒粒径分析试验结果,可得出以下结论:①粗颗粒越多(d60越大),采用相对颗粒破碎势Br量化的颗粒破碎程度越大;②较干颗粒(低含水率)由于磨损产生了更多的细小颗粒,而较湿颗粒(高含水率)由于破裂和摩擦产生了较大颗粒;③粗颗粒仅对峰值抗剪强度产生一定的影响,且粗颗粒越多,残余强度包线非线性越强;④黏聚力和内摩擦角随含水率线性减小,且低含水率试样残余强度包线非线性最强;⑤残余内摩擦角随颗粒破碎后的黏粒含量(<2μm)线性减小。提出的残余内摩擦角初步预测公式可供实际工程参考。The results of the samples with three different types of infilled joint soils（mud with fragment,mud with sand and muddy） and the ones with three different water contents（10%,7% and 3%）around the in-situ water content by the reversal direct shear tests（normal stress is between 2 MPa and 10 MPa） and particle size distribution（PSD） tests（around the shear zones） were compared to get the effects of the different initial particle size distributions and water contents on the infilled joint soil.Some conclusions are drawn as follows.①The degree of particle crushing is higher quantified by Br index（relative particle crushing potential） for the coarser particles（d60 is greater）.② Dry particles（lower water content） tend to crush to tiny particles due to abrasion and wet particles（higher water content） generate more relative large particles due to fracture or attribution.③ Coarse particles have limited effect on the peak strength;besides nonlinearity of residual strength envelope is higher for coarser particles（d60 is greater）.④ Cohesion and friction angle decrease linearly with water content;moreover the samples with lower contents have a higher nonlinear residual strength envelope.⑤ The residual friction angle decreases linearly with clay fraction;in addition,the equation proposed could be used to estimate the residual friction angle of the infilled joint soils preliminarily in practice.

关 键 词：层间错动带 反复直剪 残余抗剪强度 高压 颗粒破碎 颗粒粒径分布 

分 类 号：TU452[建筑科学—岩土工程]