土与结构接触面力学特性环剪试验研究

利用环剪仪对不同的土与混凝土接触面的力学特性进行了研究。分别对有泥皮及没有泥皮的接触面情况进行试验，并对剪切面位于黏土内的情况进行了试验。结果表明，不同接触面的应力-应变特性差异很大，泥皮的存在明显改变了接触面的性状；对没有泥皮的情况，剪切破坏面可能发生在土体内部，也可能发生在土-混凝土接触界面；而有泥皮时，破坏面始终发生在泥皮内部。试验的各种接触界面中，破坏时平均剪应力与法向应力具有较好的线性关系, 接触面强度可用摩尔-库仑准则较好地描述；当有泥皮存在时，摩擦角为没有泥皮时的63.4 %。

Experimental study of mechanical behaviour of soil-structure interface by ring shear test

The mechanical behaviour of soil-structure interface was investigated by using ring shear apparatus. The different interfaces include three types. The test results show that the stress-strain behaviour of different interfaces is apparently different. Mud-cake can change the contacting properties of interface. For the case without mud-cake, failure plane may occur in soil or on soil-structure interface. For that with mud-cake, for example drilling pore pile, failure plane is always taking place in mud-cake. In all tests, the relationship between average shear stress and normal stress is linear; and the shear strength of interface may be described with Mohr-Coulomb criterion. Friction angle of interface with mud-cake is only 63.4 % of that without mud-cake.