Numerical Analysis of Laterally Loaded Single Free-Headed Piles within Mechanically Stabilized Earth Walls

Abstract

A three-dimensional numerical analysis was conducted to evaluate the performance of mechanically stabilized earth (MSE) walls with free-headed piles installed within the geosynthetic-reinforced zone subjected to lateral loading. The numerical models were first verified with the available field test results of laterally loaded piles within MSE walls. A parametric study was conducted to investigate the influence factors on both the MSE walls and the piles, including the location of piles behind the MSE wall facing, the diameter of piles, the stiffness of reinforcement layers, and the reinforcement length ratio. Load–displacement curves, wall facing displacements, and vertical profiles of lateral earth pressure distributions behind the wall facing are discussed for each influence factor at the ultimate lateral load of the pile. Numerical results show that the ultimate lateral load capacity of piles linearly decreased with the decreased pile offset distance behind the wall facing from four times to two times the pile diameter. The lateral earth pressure distribution behind the wall facing induced by the loaded pile was nonlinear with the maximum lateral pressure located within the upper part of the wall. Tensile stiffness of reinforcement layers had a significant effect on increasing pile lateral load capacities and reducing wall facing displacements. The reinforcement length ratio had limited effects on the pile and wall performance if this ratio was greater than 1.0.