关键词: 直剪蠕变, 仪器改进, 剪应力控制, 有效面积

Abstract: Soil’s creep indicates a phenomenon that strain increases with time while keeping soil’s stress stable. Researching soil’s creep properties is very important for confirming soil’s long-term strength; and it is quite popular in recent years. However, a creep experiment costs a lot of time; therefore a simple, feasible and reliable device for soil’s creep properties will boost the research. The soil’s direct shear creep experiment is the simplest and the most intuitive way to research soil’s creep properties. But the experiment just keeps the shearing force stable, in the shearing process, the effective area reduces gradually and the shear stress increases continuously with the shear strain developing, this process is not a proper creep. By adding a simple device on the traditional experiment, the liquid’s buoyancy is used to control the shear stress to keep the shear stress stable in the shearing process. After the corresponding modification of the instrument, we had done a group of contrast tests to check the effect of shear stress controlling. The test results show that it can control the shear stress to a certain level.

Key words: direct shear creep, equipment improvement, shear stress control, effective area