用常规试验确定北京膨胀岩(土)的抗剪强度  

Determining shear strength of Beijing expansive rock(soil) by routine experiments

作　　者：杨和平[1] 符浩[1] 廖亚林[1] 尹金涛[1] 

机构地区：[1]长沙理工大学交通运输工程学院特殊土工程研究所,湖南长沙410004

出　　处：《交通科学与工程》2013年第1期1-6,共6页Journal of Transport Science and Engineering

基　　金：国家自然科学基金资助项目(50978035);交通部科技项目(2009353311060)

摘　　要：为验证膨胀土的吸附强度与膨胀力呈线性关系的研究结论,并通过常规试验确定北京西六环非饱和膨胀岩(土)的抗剪强度,在完成两膨胀岩(土)样基本性质测试和评价后,分别按设定含水率制件,开展饱和与不饱和固结慢剪试验,获得各自的有效粘聚力、有效内摩擦角及含吸附强度的总粘聚力;采用荷载平衡法,在固结仪上测得相同制件含水率两试样的膨胀压力.分析整理实测数据后得到:北京沉积型膨胀岩(土)的吸附强度与膨胀力间也呈良好线性关系;随含水率增大,试样总粘聚力呈指数减小而真粘聚力及有效内摩擦角不变;膨胀力随含水率的变化关系用指数函数描述更好.据此,建立了北京西六环非饱和膨胀岩(土)的抗剪强度公式.In order tO verify the research conclusion that there is linear relationship be- tween adsorption strength and expansive force, to gain the shear strength of unsaturated expansive rock （soil） of Beijing Western Sixth Ring Highway, on the basis of perform- ing two property experiments of expansive rock（soil）, specimens were made according to the setting moisture content. Saturated and unsaturated consolidation slow shear tests were carried out to obtain the effective cohesion, effective internal fiction angle and total cohesion including adsorption strength of the two specimens. Based on the load equilib- rium method, expansive force of the specimens under the same moisture content was ob- tained through the eonsolidometer testing. The result shows there perfectly exists linear relationship between adsorption strength and expansive force of Beijing Western Sixth Ring Highway sedimentary expansive rock（soil）, with the increase of the moisture con- tent index, the total cohesion decreased in the form of exponential function, but the ef- fective cohesion and effective internal friction angle barely changed. Exponential function could be better used to describe the relationship between the expansive force and mois- ture content. In the end, the shear strength formula was proposed for the sedimentary expansive soil of Beijing Western Sixth Ring Highway.

关 键 词：膨胀岩(土) 常规试验 有效抗剪强度 膨胀力 吸附强度 

分 类 号：U416.167[交通运输工程—道路与铁道工程]