p–y curve of laterally loaded batter piles considering effect of uplift loads

A series of model tests on a single pile are conducted under combined loading. Based on the load-displacement curves of pile head and strains of pile body obtained from model tests, the lateral soil resistance and the corresponding lateral displacement of pile body are calculated. A hyperbolic p–y curve is established to study the influences of uplift loads on the behavior of laterally loaded batter piles, and the approaches to calculate the initial subgrade reaction coefficient and the limit soil resistance are presented. This p–y curve can reflect the complex squeezing and shearing interaction between the batter piles and the surrounding soils under combined loading. Based on the established p–y curve, the influences of pile-top restraint conditions and uplift loads on the load-deformation behavior and internal force distribution of laterally loaded batter piles are analyzed. The results of the analysis show that: (1) Whether the pile head is free or fixed, the lateral displacement, shear force and bending moment of the positive batter piles decrease with the increase of the uplift loads, while the opposite characteristics are observed for the negative batter piles. (2) Under the same load condition, the lateral displacement, bending moment and shear force of the positive batter piles are less than those of the negative inclined ones. (3) The lateral displacement, bending moment and shear force of the batter piles under the fixed pile head are less than those under the free one.