摘要
考虑渠道浅层土体的实际应力状态,开展了一系列低围压下的三轴固结不排水剪切试验,分别研究了干湿循环、冻融循环和干湿-冻融循环三种环境作用对取自黑龙江大庆的膨胀土的应力-应变关系和抗剪强度的影响。结果表明,在低围压下:未经历和经历了三种循环作用的试样,其应力-应变曲线总体上表现为弱应变软化型或应变稳定型;相同围压下,经历了三种循环作用的试样均随作用次数的增加,产生破坏强度明显降低的现象,其中经历干湿-冻融循环的试样在作用8次后趋于稳定,其试样破坏强度降低的幅度最大;经历三种循环作用后,试样黏聚力均呈指数型衰减,而内摩擦角变化不大,其中经历干湿-冻融循环作用的试样黏聚力衰减程度最大。
Considering the actual stress state of shallow soil,a series of triaxial consolidated undrained sheer tests were conducted on an expansive soil from a channel slope in Daqing,Heilongjiang Province,China under low confining stresses to investigate the influences of wetting-drying and freezing-thawing cycles on the stress-strain behavior,and shear strength of Daqing expansive soil.The results showed that:The stress-strain behavior of the expansive soil specimens is generally strain-softening.As the number of cycles increases,the shear strength of specimens decreases significantly.The shear strengths of the specimen softening undergoing eight wetting-drying and freezing-thawing cycles are basically stable,and suffering greatest alterations on shear strength.After cyclic treatments,the cohesion of samples decreases exponentially and those subjected to wetting-drying and freezing-thawing cycles suffer greater alterations on cohesion,while the internal friction angle remained relatively constant.
作者
高小云
刘家国
赵贵涛
邹维列
GAO Xiaoyun;LIU Jiaguo;ZHAO Guitao;ZOU Weilie(School of Civil Engineering,Wuhan University,Wuhan,Hubei 430072,China;Shenzhen Geological Bureau,Shenzhen,Guangdong 518023,China)
出处
《水利与建筑工程学报》
2019年第2期24-28,共5页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金项目(51779191)
关键词
膨胀土
干湿-冻融循环
低应力
应力-应变关系
抗剪强度
expansive soil
wetting-drying and freezing-thawing cycle
low confining stress
stress-strain behavior
shear strength
作者简介
高小雲(1993-),女,广西玉林人,硕士研究生,研究方向为非饱和土特性。E-mail:yun23023@163.com;通讯作者:刘家国(1970-),男,广东深圳人,高级工程师,主要从事非饱和土特性、地基处理等方面的科研工作。E-mail:zwilliam@126.com.
