Physical modeling of landslide stabilization methods in an overconsolidated clay

This paper describes some of the main results of physical modelling tests performed on retaining structures. The modelling arose from the design of stabilising structures for a landslide with a natural slope angle of 10°, a thickness of about 15m, a 90 m wide and 600m long extension, which occurred in overconsolidated clay. The medium plasticity inorganic clay soil was characterised by a shear resistance peak angle, ’P = 24.7° and a residual angle ’R = 10.5°. Two types of stabilising structure models fixed into the subsoil, were adopted: the first, consisted of a diaphragm wall and the second of three aligned piers; both models were instrumented with strain gauges. The sliding block was mechanically pushed against the structure up to failure, in order to assess the behaviour of the structures in displacing ground. This paper presents details of the performed tests, the procedures that were adopted and an analysis of the gathered results according to “empirical based” and “pressure based” design methods.