Abstract: Based on the Boussiesq solution, a method for computing the distribution of the stress and the deformation in homogeneous soil with several different kinds of loads including rectangular loads and strip loads acting exclusively on the surface of a half elastic space is given by means of integration of the Boussiesq equations of a concentrated force acting on the surface. The integration is realized by numerical integration, the composite Simpson’s rule, with dividing the acting area of the distributed loads into numerous tiny rectangles. Meanwhile, the deformation of discrete pile elements, which derives from the finite difference analysis, is given with pile subjected to concentrated force or moment on the pile top. In the same way, deformation of discrete soil elements around the pile is given based on the Mindlin solution. With the combination of the deformations of pile and soil elements, the interactions between discrete pile-soil elements are calculated to solve the responses of “active pile”. Then, combining the analysis of soil in free field and that of “active pile” mentioned above, with the displacement of free field imposed on the pile, we thus get solutions of the stress, moment and deformation along the passive pile. Consequently, a method which can be used to calculate free-field movements and stress of soil, strain and stress of “active pile”, as well as the responses of passive piles subjected to different kinds of external loads acting at the surface of soil, is given based on the analysis above. The validity of the method proposed above is testified. A pile subjected to a rectangular uniform load at the surface of soil nearby is taken as an example. Comparisons are made between results from the method proposed in the paper and those from finite element method (FEM), which testifies the method is reasonable. Furthermore, a project case of piled bridge abutment is taken for verification. Results from the method given above are in good accordance with the original data from the in-situ test from the published paper. Therefore, the method could be used to calculate the response of bridge piles with embankment loads nearby.

Key words: passive pile, loading at bridge-head, bridge pile foundation, elastic theory