Deducing Pile Responses and Soil Reactions from Inclinometer Data of a Lateral Load Test

Abstract

This paper presents a regressive model to deduce the internal forces and soil reactions of a laterally loaded test pile from the data of inclinometer measurements. This model simulates the distribution of bending moments of the pile by using a composite function of which the upper part is modeled by a polynomial and the lower part is modeled by the characteristic function of an analytical solution for a semi-infinite pile supported by uniform Winkler soil springs. Through successive regressive analyses, the optimal composite function obtained can effectively simulate the pile responses including the deflections, bending moments, shear forces, and the associated soil reactions. For verification, both the solution of a finite element analysis and the results of an in-situ load test have been adopted and the results of regressive analyses can satisfactorily obtain the pile responses. In addition, on the basis of curves of pile deflection and soil reaction deduced from the results of the pile test, a set of site-specific p-y curves can thus be established. Finally, a parametric study has shown that accurate estimate of moment-curvature relationship of a pile section is essential to the accuracy of the deduced pile internal forces, soil reactions, and p-y curves.