Experimental study on interfacial shear properties of steel plate, polymer and soil

The shear properties of interfaces between polymer and different media are investigated based on the direct shear tests. The effects of moisture content of soil, normal stress, interface types, polymer density and molding method on the interfacial shear strength are all examined. The results show that the steel plate-polymer interface exhibits brittle failure mode, which is different from that of other interfaces. The shear strength of different interfaces depends upon the polymer density, normal stress and moisture content of soil. The interfacial shear stress increases with the increase of the polymer density and normal stress, but decreases as the moisture content increases. Given the normal stress and moisture content, the shear strength of the non-preformed polymer-soil interface is greater than that of the preformed polymer-soil interface. Nevertheless, with the increase of the moisture content, the influences of polymer-forming methods on the shear strength of the polymer-soil interfaces are gradually weakened. Given other conditions the same, the shear strengths of the steel plate-polymer interface, polymer-soil interface, soil itself, and steel plate-soil interface decrease in order. After using the polymer, the interfacial shear strength is increased by 73%, 108%, 125% and 115%, respectively. The steel plate-polymer-soil interface mechanically outperforms the steel plate-soil interface in terms of the shear strength.