Load-settlement response of circular footing resting on reinforced layered system

Abstract

Removal of unsuitable soil and replacement with a strong material is one of the oldest and simplest ground improvement techniques. During this process, a layered soil system with a strong layer overlying a weak layer is achieved. Studies on the load-settlement response of footing on such layered system are limited. An experimental study is carried out to obtain the load-settlement response of a model circular footing resting on (a) unreinforced aggregate layer overlying a sandy soil layer, and (b) geogrid-reinforced aggregate layer overlying a sandy soil layer. A large-scale test chamber of size equal to 1m × 1m × 1m is used to perform the experiments. Actuator of 10T capacity is used to apply the loads in a displacement-rate controlled mode. A plate vibrator is used to prepare uniform sand and aggregate layers inside the test chamber. Relative density equal to 70% is maintained for both the layers during the entire test program. The improvement in the load carrying capacity of model footing with the increase in the thickness of aggregate layer and with the introduction of geogrid reinforcement in the aggregate layer is proposed in the study.