Abstract: The interaction between soil and geosynthetics is an important issue in the research of reinforcement mechanism, and the properties of reinforcement material are key parameters in the design of reinforced-soil structure. A new multifunctional soil-geosynthetics testing machine has been developed on the basis of conventional direct-shear test apparatus. The machine consists of two sets of servo motor, automatic control and data acquisition system, and a set of shear box with dimension of 600mm×300mm×300mm, etc. Direct-shear test, pull-out test, confined-tension test and confined-creep test can be conducted on the machine through several auxiliary means and control modes. Furthermore, the sand-confined tensile strength and creep properties of different geogrids were tested and compared. The contribution of geogrid-soil interaction to the strength of soil-geosynthetics was also analyzed. The tests validated that the machine has good operability and accuracy.

Key words: soil-geosynthetics testing machine, servo control, interaction of soil-geosynthetics, pull-out test, confined tension test, confined creep test