Approach to the correlation factors for static and dynamic pile load tests

摘要

In determining the design values of a pile resistance from the results of static and dynamic pile load testing the measured values R-c;m of the pile capacity have to be initially mitigated by correlation factors zeta to derive the characteristic pile resistance R-c;k. With the correlations factors the influence of the spatial variability of the subsoil, but also of the uncertainties arising from the execution and evaluation of the pile load tests on the derivation of the characteristic pile resistance from the measured values of a single or limited number of test loads is taken into account. An analysis of the existing approach implemented in handbook Eurocode 7, Volume 1, indicates shortcomings particularly with respect to the sole dependency of the correlation factors on the number of performed load tests. In this regard approaches for an evolution of the present regulations are discussed. In addition, a proposal for reduced zeta-values for the special case that dynamic load tests are executed at all piles of a pile foundation ("n = n") is presented.