RELIABILITY STUDY OF THE FOUNDATON OF A HYPERSTATIC VIADUCT
Foundations, Piles, Reliability analysis, Failure probability, Monte Carlo Simulation
Reliability analysis is a tool that allows to quantify the uncertainties involved in the design and execution of structures in civil construction, allowing to know the probability of ruin and the adoption of safety factors most appropriate to the maximum risk allowed. The purpose of this research is to determine the probability of failure of pile foundations of a viaduct considering the vertical actions. Reliability analysis was performed using the Cintra and Aoki Method (2010) and the Monte Carlo Simulation, using the dynamic formulas of Chellis (1951) and Smith (1960) modified by Aoki (1996) to obtain the vertical resistances. The input parameters in the formulas were obtained in the execution phase of the driven metallic piles, namely, the nailed length (L), the set (S) and the rebound (K). Vertical loads were determined following NBR 7187/2003, NBR 7188/2003 and the Engesser-Courbon load sharing method (Courbon, 1940). Furthermore, all these parameters were tested under nine probability distributions: normal; lognormal; exponential; beta; gamma; chi; Laplace; Gumbel and Weibull. The parameters were verified with the Kolmogorov-Smirnov hypothesis test and the Q-Q graphic test. The ruin probability values found were very close, with low variance and a maximum probability of 0.04% at the upper limit, considering all methods and formulations.