中文摘要：

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纸并不是一个常量，而是吸力区间内的连续减函数。

英文摘要：

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.