Characterizing breaking wave slamming loads on bridge piers with probabilistic models of slamming maxima, rise and decay times

Abstract

The piers of sea-crossing bridges always suffer from considerable breaking wave loads. But the uncertainties and variability of wave slamming maxima and time history have yet been understood quantitatively. This paper conducted a series of experiments in a wave flume to investigate the slamming load of breaking waves on bridge piers with different cross-sections. Four piers with three kinds of cross-sections under three breaking wave conditions were employed in the experimental program. The time history of breaking wave slamming load was characterized by three parameters, i.e., slamming maxima, rise and decay times. To account for the statistical variability of breaking wave load, a pair-copula decomposed trivariate joint probability model was developed to determine the joint distribution of slamming maxima, rise and decay times. The effects of pier geometry on the probabilistic modeling of slamming maxima, rise and decay times are analyzed based on the experimental results. The slamming maxima, rise and decay times follow the generalized extreme value (GEV), log-logistic, and gamma distribution, respectively. Their marginal and joint probabilities are sensitive to the pier shape. This study provides an effective probability method to characterize breaking wave slamming loads based on the experimental results.