Pile load transfer from static load test inversion

Abstract

This paper presents an inversion scheme to estimate the distribution of load in a deep foundation from the load–movement curve measured at the head. The method may be useful in situations where static load tests have been performed on test piles that are not instrumented with strain gages or telltales, or the instrumentation data are unreliable. An inversion approach is described in detail that includes a non-linear ‘t–z’ analysis combined with a genetic algorithm that is used to optimise the solutions. The inversion approach is tested using three high-quality pile load test cases from the literature. The pile load distributions estimated from the inversions were in generally good agreement with the measured data. The inversion approach was also effective identifying the ‘true’ load distribution in a pile where residual loads were present.