Probabilistic analysis of pile deflection under lateral loads

C.I.Tech and B.K.Low

School of Civil and Structural Engineering, Nanyang Technological University, Singapore

The deflection and bending moment of laterally loaded single piles are studied using the p-y curve concept. Instead of implementing the finite element or finite difference methods, a simple yet equally rigorous numerical procedure based on spreadsheet optimization is presented for solving the soil-pile interaction problem. The accuracy of the analysis is validated by comparison with Hetenyi’s solution for the special case of linear and uniform modulus of subgrade reaction. The deterministic formulation is then extended to probabilistic analysis by computing the Hasofer-Lind reability index with respect to performance function based on pile head deflection. Probability distribution plots of pile head deflection are obtained, and compared with Monte Carlo simulations.

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