Bearing Characteristics and Analysis Methods of Horizontally Loaded Single Piles Under Clay Slopes

With the increasing construction of pile foundations on mountain slopes, the asymmetric stress field induced by slopes significantly reduces the lateral soil resistance of piles. Most existing studies focus on piles located at slope crests, and there is an obvious gap in p-y curve calculation methods for piles embedded in clay slopes. In this study, model tests of single piles in clay slopes with slope angles of 0°, 15°, and 30° are carried out. The test results reveal that the increase in slope angle aggravates the horizontal displacement and bending moment of piles and moves the pile rotation point downward. Numerical model is adopted to extract p-y curves at various embedded depths and slope angles. It is found that rising slope angles continuously degrade the initial stiffness and ultimate soil resistance of p-y curves, and such degradation weakens with increasing embedment depth. The core innovation of this paper is establishment of a modified p-y curve model considering slope effects. A simplified analytical method for slope piles is further proposed based on the load transfer method. The prediction errors of this modified model are within the allowable engineering range, which can provide a reliable analytical tool for calculating the lateral bearing capacity of pile foundations in clay slopes.