Performance of Axially Loaded-Piled Retaining Wall: Experimental and Numerical Analysis

Abstract

The piled wall has other applications in addition to supporting the excavation, such as use as part of the permanent work/foundation. It also can be used to reduce or eliminate the need for a separate foundation by carrying all or a portion of the superstructure loads, especially in urban areas. In this study, the potential benefits of using a piled retaining wall to resist the axial load were investigated. A series of plane-strain small-scale model tests on a piled retaining wall embedded in sand under axial loads was performed in the laboratory. The influence of the penetration depth, pile stiffness, and sand relative density on both ultimate axial capacity and deformation behavior of the piled system was evaluated. The results indicate that the ultimate axial capacity of the tested piled wall was remarkably increased with the increase of both penetration depth and soil relative density. When the soil relative density was varied from 50 to 88%, ultimate axial piled wall capacity increased by 72% for the piled wall system installed with a penetration depth of three times the free height and high stiffness. The ultimate axial capacity of the piled wall had a significant effect on the maximum horizontal deformation at failure, in the range of 0.14% of the total piled wall height. Numerical analysis showed that the existence of surcharge stress in the active zone behind the axially loaded-piled wall substantially reduced the ultimate axial capacity of the piled wall by 50%, with remarkable increase in lateral wall deformation and maximum bending moment.