进行了粗粒土与结构面分别在夹膨润土泥皮、粘土泥皮以及无泥皮条件下的大型单剪试验，揭示了不同泥皮情况下接触面的力学特性与机理。试验结果表明，不同泥皮种类对粗粒土与结构面的强度有重要影响，夹有膨润土泥皮时，粗粒土与结构面的剪切强度显著减小，最大减幅可达45%，而夹有粘土泥皮时其最大减幅只有10%，远小于膨润土泥皮；试验测定的夹有膨润土泥皮时的摩擦角仅为夹有粘土泥皮时的60％左右。剪切破坏时，同一高度处，切向位移随法向应力的增大而增大；同样的法向应力及高度处，夹有膨润土泥皮时的切向位移小于夹有粘土时的切向位移，而法向位移相对要大些。此外，无泥皮低法向应力下，出现明显的剪胀现象，而泥皮条件下均表现为剪缩。

The mechanical behavior and mechanism of the interface between structure and coarse grained soil are investigated through simple shear tests on the conditions of bentonite slurry, clay slurry and without slurry, respectively. The results indicate that different kinds of slurry have important influence on shear strength. Compared with the interface without slurry, the shear strength with bentonite slurry reduces by 45% approximately, significantly more than clay slurry which reduces by 10%. The value of the friction angle with bentonite slurry is about 60% of that with clay slurry. Shear displacement increases as upright stress increases when reaches its failure states at the same height, and shear displacement with bentonite slurry is smaller than that with clay slurry when with the same upright stress and height. The upright displacement with bentonite slurry is greater than that with clay slurry under the same upright stress. In addition, shear dilatation is apparent under the low normal stress when without slurry. Otherwise, it appears as shear contraction.

中央高校基本科研业务费专项资金项目(2010B14814)；国家自然科学基金委员会、二滩水电开发有限责任公司雅砻江水电开发联合基金项目(50639050)；水利部公益性行业科研专项经费项目(200801133)；河海大学岩土力学与堤坝工程教育部重点实验室开放基金(GH200804)