中文摘要：

运用最新研制的80t三维多功能土工试验机,对工程中常用的粗粒土与人造粗糙钢板构成的接触面在常刚度法向边界条件复杂加载路径下的三维力学特性进行了试验研究,分析总结了粗粒土与结构接触面在常刚度法向边界条件下的基本规律。试验结果表明：接触面受剪切时发生了明显的法向位移,从而直接导致了法向应力和抗剪强度的降低;法向位移可分为遵循不同规律的可逆和不可逆两部分;十字加载路径下的接触面摩擦角略大于圆形加载路径;单向往返和十字加载路径下接触面力学特性较为相似,但与圆形加载路径有明显不同。

英文摘要：

A series of tests are performed with a new apparatus called 80 t 3D multifunction apparatus for soil mechanics （3DMAS） to study the 3D cyclic behaviors of the interface under constant normal stiffness condition, which is between a rough steel plate and coarse-grained soils generally used in geo-engineering. Based on the results, the behaviors of the interface are concluded. The test results indicate that： 1） the normal displacement due to the shear application is obviously observed; 2） the increase of the normal displacement leads to the reduction of normal stress and shear strength; 3） the normal displacement can be divided into reversible and irreversible parts; 4） the friction angle of the interface in cross-shear path is a little larger than that in circle-shear path; 5） the behaviors of the interface in cross-shear path are similar to those in two-way shear path, but different from those in circle-shear path.