南方短时冻土抗剪强度指标C、φ值的试验研究  

Experimental investigation on shear strength parameters C and φ for a temporarily frozen soil in South China

作　　者：王永忠[1] 刘雄军[2] 艾传井[2] 彭玉环[2] 

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]中国电力工程顾问集团中南电力设计院,湖北武汉430071

出　　处：《武汉大学学报（工学版）》2010年第2期198-202,共5页Engineering Journal of Wuhan University

基　　金："十一五"国家科技支撑计划项目(编号:2008BAC47B02)

摘　　要：以2008年南方地区发生的极端冰雪灾害使土体短时冻结并融化后造成的地质灾害为背景,通过模拟极端冰雪环境,研究在短时冻结-解冻条件下,冻融作用、温度和含水量等因素对南方地区粉质粘土的抗剪强度指标C、φ值的影响.对不扰动土及重塑土试样进行大量直接剪切试验和环境扫描电镜试验,试验发现冻融前后土的C、φ值和微观结构均有一定的变化,并分析了正冻结土与正解冻土在不同温度及含水量下C、φ值的变化规律.The temporary freezing and thawing of soils under the extreme snow and ice conditions in South China in 2008 induced numerous geologic hazards.With this background,the impacts of freeze-thaw action,temperature and water content on the shear strength parameters C and φ of a silty clay in South China were investigated by simulating the extreme snow and ice activities.A large number of direct shear tests were performed on both undisturbed soil samples and remolded soil samples,together with environmental scanning electron microscope tests on undisturbed ones.The testing results show that both the shear strength parameters C and φ,and the microstructure of the soil are significantly influenced by the freeze-thaw action.The variations of the cohesion C and the friction angle φ with temperature and water content were further analyzed for freezing soil and thawing soil.

关 键 词：短时冻土 抗剪强度 冻融作用 粘聚力 摩擦角 

分 类 号：TU411.7[建筑科学—岩土工程]