Modified Calculations of Lateral Displacement and Soil Pressure of Pile Considering Pile–Soil Interaction under Cyclic Loads

Abstract

A reciprocating low-cycle pseudostatic loading test on four prestress high-strength concrete (PHC) pipe piles was performed to study their failure modes and seismic behaviors. The distributions of lateral deformation and soil pressure along the piles as well as their analysis methods were studied. The test results show that with an increase in the embedded depth of pile, the soil pressure around the piles initially increased up to the maximum and then decreased or even reversed slightly at a certain depth. The pressure at shallower soil increased rapidly, up to nearly the ultimate passive earth pressure, while the pressure at the deeper soil increased relatively slowly. The results further indicate that the strain transformation method and m method were only appropriate for calculating the lateral displacements of piles under linear and small deformation but not suitable to calculate lateral displacement of piles under large deformation. Moreover, although the p-y curve method took into account the nonlinearity of soil, the calculated lateral displacement and soil pressure of pile still showed a significant difference with the test results, especially under large deformation. Furthermore, modified calculations of lateral displacement and soil pressure of pile were proposed based on regression analysis on the test results and existing p-y curve methods, respectively, and calculated results showed a good agreement with the test results in terms of lateral displacements and soil pressures. Therefore, they were recommended for analyzing the soil-pile interaction for pile foundations in integral abutments jointless bridges (IAJBs).