Abstract：A simplified approach for nonlinear analysis of the load-displacement response of a single pile and pile groups embedded in multilayered soils is presented. Two models are adopted in the proposed method. One model uses a softening nonlinear relationship to simulate the degradation behavior between pile-soil relative displacement and unit skin friction developed along the pile-soil interface；and the other model adopts a bilinear displacement-unit end resistance relationship to capture pile end response. A highly effective iterative computer program is developed to analyze a single pile response using the proposed two models. Furthermore，based on the settlement of a single pile derived from the proposed computer program and the equivalent pier method，a simplified calculation approach for average settlement of pile groups is presented. Comparisons of the load-settlement responses demonstrate that the proposed method is generally in good agreement with the field-observed behavior and the calculated results derived from other approaches.
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2013, Vol. 32 
