Dynamics-based interpretation of the interface friction test at the inclined plane

The inclined plane test is used to determine either soil–geosynthetic or geosynthetic–geosynthetic interface properties, especially in cases where the stress normal to the interface is small. The design of sloped cap covers for landfill sites or along the banks of reservoirs and canals necessitates this type of test. The interface friction test, when performed in accordance with the current European test standard, yields only the interface friction angle. In this paper, the potential for drawing considerably greater information from the test is demonstrated. This procedure requires the interpretation of an entire dynamics phase, in particular the phase during which the upper box is engaged in uniformly accelerated movement. Two new parameters are also defined, called the angles of static friction and dynamic friction.