PROBABILISTIC ANALYSIS OF BEARING CAPACITY OF PILES WITH VARIABLE PARAMETERS IN CPT TEST AND CALCULATION ACCORDING TO THE REQUIREMENTS OF EUROCODE 7 (EN 1997-1: 2004) REGULATIONS

A probabilistic concept for determining pile bearing capacity is presented, taking into account the variability of CPT test parameters and methodology of calculation according to the requirements of Eurocode 7 (EN 1997-1: 2004). Based on a single initial (real) CPT test, a larger number of generated (simulation) CPT tests are introduced drawn from solutions of statistics and probability theory. Research has found that the best solutions are achieved using the DA 2 design approach for n(CPT) >= 10 tests. Taking into account the deterministic and probabilistic approach in the analysis of pile bearing capacity, it is found that for the DA 2 design approach, the ratio of pile bearing capacity obtained from simulation and the capacity as determined through three methods (Mazurkiewicz, Van der Veen and hyperbolic approximation) is R-c,(d)/P-u = 1.148. Using the reliability index, the following values of partial resistance factors are obtained: gamma(b),(ss) approximate to 1.1, gamma(s),(ss) approximate to 1.1, which also points to the DA 2 design approach.