Physical modelling of a soil wall reinforced with extensible and inextensible reinforcement

Abstract

Since the rise of geosynthetics in industry and the subsequent challenge posed to conventional steel reinforcement, it was pertinent to directly compare the performance of a soil wall reinforced with two different types of reinforcement under surcharge loading. In this paper, four small-scale vertical soil walls were constructed and tested in the geotechnical centrifuge with extensible (PVC) and inextensible (steel) reinforcement strips. Surcharge loads were applied onto the retained soil behind the walls at a centrifugal acceleration of 30 G. The models were constructed with metallic U-shaped facing panels and backfilled with fine silica sand. The horizontal displacement of the facing was measured with displacement transducers, the soil strain was captured using particle image velocimetry analysis, and the reinforcement strains were recorded with conventional strain gauges and fibre optic technology by means of fibre Bragg gratings. The results of the experiments showed that the soil walls reinforced with inextensible reinforcement exhibited rigid behaviour during loading, deformation of the wall facing was resisted with a wall stiffness four times larger than with extensible reinforcement, and the reinforcement strains were one order of magnitude less than the extensible reinforcement.