Experimental analysis of bearing capacity failure of geosynthetic-reinforced soil walls

Small- and large-scale 1g experiments were conducted to investigate the bearing capacity failure of geosynthetic-reinforced soil walls. The small-scale experiments (1/10) provided fundamental insights into the development of failure based on digital image correlation analysis. Since these tests suffered from scale effects, large-scale tests (1/1.67) were performed to quantify the ultimate load-bearing capacity of a 1.2 m high wall. A vertical load was applied on top of the structures and internal soil movements and stresses, wall deformations and reinforcement strains were measured. The experimental results revealed that the failure was initially triggered at the rear end of the bottom reinforcement. The wall rotated to the backfill and the ground surface in front of the wall was uplifted. The results confirmed the quasi-monolithic behaviour of the reinforced zone. A multi-body failure mechanism was observed below the base of the wall, consisting of an active and a passive wedge connected by a transition zone. Important scaling factors were discussed using the two different scales which has shown important conclusions that are relevant for experimental studies. The analytical calculations revealed that a reduced reinforcement length needs to be considered in the analytical approach to predict a rather conservative load-bearing capacity.