Lateral bearing characteristics of inclined pile-cap system installed in sandy ground

The lateral bearing characteristics of inclined pile-cap systems installed in sandy soil are comprehensibly studied via a series of laboratory model tests, and the influences of inclination angle and flexural rigidity of pile on the lateral displacement at pile top and the distribution of pile bending moment are analyzed. Based on the model tests, a suite of three-dimensional finite element analyses are performed, and the favorable comparison of the test and numerical results convinces the capability of the adopted finite element analysis procedure in replicating the stress and deformation characteristics of the inclined piles in the model tests. Subsequently, a number of numerical parametric analyses based on the prototype models are implemented, accounting for the elastic-plastic mechanical properties of the pile, as well as the variations in elastic modulus of soil, flexural rigidity and length of the pile. The analysis results show that the variation in the elastic modulus of soil has a more significant effect on the lateral bearing capacity of the inclined pile-cap system than the change in pile flexural rigidity. When the pile length is less than 25 times the pile diameter(D), the increase of pile length can effectively reduce the lateral displacement response at the pile top. Otherwise, increasing the pile length has negligible effects on enhancing the lateral performance of the inclined pile-cap system. Furthermore, the multivariate regression analysis is performed based on the test data of lateral displacement at pile top, from which a semi-empirical equation can be derived. The performance of this semi-empirical equation is favorably examined by both the relevant experimental data and the numerical parametric analysis results, which likely provides a useful reference for the design and analysis of the inclined pile-cap system in sandy ground.