Load-Deformation Behavior of Geosynthetic-Reinforced Retaining Walls with Limited Fill Space Under Static Footing Loading

摘要

Geosynthetic-reinforced retaining (GRR) walls have been increasingly built with limited fill space, which has posed challenges for designing such walls with satisfactory performance, especially under surface loading, such as bridge and building foundations. This study performed a series of laboratory model tests to investigate the performance of GRR walls constructed with limited fill space under strip footing loading. The devised experimental program consisted of constructing nine model tests with different retained medium distance, geosynthetic-reinforced fill width, and reinforcement layout. In each model test, a load was applied on the top of the wall through a 200 mm wide rigid plate to simulate a strip footing. Marks on facing units and the loading plate were installed to measure wall deformations and footing settlements, respectively. The test results show that limiting the size of the retained medium and the reinforced fill affected the internal stability of the wall, the wall deformation, and the footing settlement. Reduction of the reinforced fill width from 0.5H to 0.3H (H is the wall height) resulted in excessive wall deformation and footing settlement, and even sudden failure of the model wall. On the other hand, the test results reveal that connecting geosynthetic reinforcement to the stable retained medium resulted in substantial reduction in the deformation of the wall facing and the settlement of the footing. The test results also demonstrate that bending geosynthetic reinforcement upward along the back of the reinforced fill enhanced internal stability and resulted in considerable reduction in the lateral deformation of the wall facing and increase in the bearing capacity of the footing.