中文摘要：

理想接触面力学特性的研究对其离散元数值模拟具有佐证材料和推动意义;运用自主研制的80 t大型三维接触面试验机对球形粒状介质与钢板形成的理想接触面三维单调、循环剪切力学特性进行分析和总结。试验结果表明理想接触面与实际粗粒土与结构接触面力学特性有较大不同。理想接触面亦产生明显的剪切体变,循环剪切时可分为可逆性和不可逆性两部分;不可逆性剪切体变主要由颗粒调整、孔隙减小所致;可逆性剪切体变主要由颗粒爬升、翻滚造成,受剪切路径影响明显;理想接触面剪切硬化现象不明显,切向应力-切向位移关系呈现明显非线性,曲线形式亦受剪切路径影响;接触面抗剪强度与法向应力关系符合莫尔-库仑准则,其摩擦角？i约为20.2°,小于粒状介质本身内摩擦角;剪切路径对主应力比时程曲线形式影响明显,对主应力比峰值影响不大。

英文摘要：

Applied with self-developed three-dimensional interface test apparatus,three-dimensional monotonic and cyclic shear mechanical behaviors of ideal spherical granular media-steel plate interface are investigated,which is direct proof and of great significance to its numerical simulation using discrete element method.The test results indicate that the mechanical behavior of ideal interface is very different from that of actual coarse grained soil-structure interface.Ideal interface also presents obvious shear volumetric change,which can be divided into irreversible and reversible components during cyclic shearing.The irreversible component is mainly yielded by particle rearrangement and void reduction.The reversible component is induced by particle climbing or even rolling;and shear path has an obvious influence on reversible component.The hardening behavior of ideal interface due to cyclic shear application is not so apparent as actual gravel-structure interface for little particle crushing.The shear stress-shear displacement relation curves present obvious nonlinearity and the curve patterns are also influenced by shear path.The relationship between shear strength and normal stress of interface can be described with Mohr-Coulomb criterion,in which the friction angle of the interface ？i is approximately 20.2°,which is smaller than internal friction angle of granular media.Shear path has a notable influence on cyclic history curve patterns of principal shear stress ratio of ideal interface,while it has a little influence on peak value of principal shear stress ratio.