非饱和膨胀土强度及变形特性试验研究  

Experimental study on strength and deformation of unsaturated expansive soils

作　　者：韩华强[1] 陈生水[1] 郑澄锋[1] 

机构地区：[1]南京水利科学研究院岩土工程研究所,江苏南京210024

出　　处：《岩土工程学报》2008年第12期1872-1876,共5页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(50479031);南京水利科学研究院青年基金项目(Y30603)

摘　　要：利用可控吸力的VJ非饱和三轴仪对新疆膨胀土的强度和变形特性随干密度和吸力的变化规律进行了试验研究,结果表明:非饱和膨胀土的胀缩特性不仅取决于其干密度及所承受的围压,而且还与其吸力大小密切相关,且随吸力增大其剪胀特性增强。非饱和膨胀土的吸力和干密度对黏聚力影响也十分明显,随吸力和干密度增大,非饱和膨胀土的黏聚力呈非线性增大,且增幅明显,而对有效内摩擦角则几乎没有影响,Fredlund双变量理论中的吸力内摩擦角?b并不是一个常量,而是吸力区间内的连续减函数。The strength and deformation of Xinjiang expansive soils with different dry densities and different suctions were studied by use of the VJ unsaturated tri-axial apparatus. It was found that, the swell-shrinking of unsaturated expansive soils not only depended on the dry density and the confining pressures, but also closely related to the suction, and the dilation increased with the increase of the suction. In addition, the cohesion of unsaturated expansive soils increased nonlinearly and obviously with the increase of the suction and dry density. However, the variation of the suction and dry density almost did not influence on the effective angle of the internal friction. The ψb of Fredlund＇s double variables theory was a continuously decreasing function in the interval of the suction instead of a constant.

关 键 词：非饱和膨胀土 三轴试验 强度 变形 

分 类 号：TU411[建筑科学—岩土工程]