Nonlinear Response of Passively Loaded Piles Founded in Soft Bangkok Clay

Embankment construction on soft clay can result in the development of significant lateral ground movement. When the pile is installed adjacent to this unstable embankment, it may experience unexpected lateral passive loading along its length and may cause the integrity problem of the superstructure. A lot of numerical and experimental research works have been conducted for better understanding of the behavior of passively loaded pile. However, the nonlinear response of piles subjected to horizontal ground movement is difficult to analyze with two-dimensional technique since the passively loaded piles are truly three-dimensional problem. In order to investigate the complex soil-pile interaction, the three-dimensional finite element analysis was employed in this study. The passive p-δ curves are presented to account for a nonlinear response of piles as the common p-y curves may not properly describe the actual behavior of piles subjected to lateral ground movement. It was found that the generated p-δ curves were dependent on pile spacing; when pile spacing decreased the passive p-δ curves stiffened, whereas the active p-y curves softened. A better understanding of behavior of passively loaded piles adjacent to an embankment constructed on soft Bangkok clay was achieved.