筋-土界面力学特性的水平循环剪切试验研究

加筋材料与土界面力学特性是加筋土结构设计和稳定性分析的重要依据。在大型多功能界面剪切仪上，进行了土工格栅和标准砂界面的水平循环剪切试验，分析循环荷载作用下筋-土界面力学特性，研究循环荷载特征对界面剪切力和法向位移的影响，探讨水平循环荷载作用下筋-土相互作用规律。结果表明，随循环次数增加，剪切力-位移关系曲线逐渐重合，剪切力峰值变化不明显，界面剪切模量增大并趋于稳定；循环剪切位移幅值和剪切速率对剪切强度的影响不明显，但对试样法向位移有较大影响；水平循环剪切过程中试样发生明显的法向位移，加筋可有效限制试样的竖向变形。

Research on the mechanical behavior of soil-reinforcement interface by horizontal cyclic shear test

The mechanical properties of soil-reinforcement interaction are of utmost importance for the design and stability analysis of reinforced soil structures. Using large-multifunctional interface shear apparatus, a series of horizontal cyclic shear tests are carried out between geogrid and standard sand. The mechanical behavior of geogrid-soil interface is recorded and analyzed. Then the influences of the characteristics of horizontal cyclic load on the interface shear strength and vertical displacement are studied. In the end, the mechanism of soil-reinforcement interaction under horizontal cyclic load is investigated. The results of this research indicate that the curves of shear force and displacement merge into one curve gradually with the increase of shear cycles; the change of shear stress summit is not obvious; the interface shear modulus increases with the cyclic load and reaches stable. The influence of the amplitude and velocity of shear displacement on shear strength is not evident; but the amplitude and velocity of shear displacement have significant effects on the vertical displacement of the samples during horizontal cyclic shear tests. In the process of horizontal cyclic shear tests, the sample takes obvious vertical displacement. The reinforcement has effective confinement to the vertical deformation of test samples.