APPROXIMATE ELASTIC-PLASTIC SOLUTION FOR AXIALLY LOADED PILES

An approximate elastic perfectly plastic solution in a closed form for axially loaded piles based on the t-z curve method, is presented. The closed-form solution allows prediction in a very simple way of vertical pile movements and settlement at the pile head as well as the value of the axial load at a certain depth from the ground surface. Differently from elastic solutions, the method can take into account the nonlinear behavior of the load-settlement curve. Because of the approximation made to derive simple expressions in a closed form, the method does not apply to situations where a significant portion of the working load is derived from end-bearing capacity. However, when the analysis is restricted to design loads and the choice of soil parameters is appropriate, the solution presented can give reasonable results. This is confirmed by comparisons with data from full-scale pile tests taken from the literature.