Dependence models and Gamma process for single-defect deterioration of a rock-armored groyne under ship-wave attack

Abstract

Infrastructures are facing growing challenges due to their aging process while climate change and evolution of traffic and shipping fleets are increasing the uncertainty of loadings in the future. This study proposes a method to assess the survivability of structures with gradual deterioration under changing loading scenarios based on field data. The methodology is applied to the armor deterioration of a rock-armored groyne under ship-wave attack. First, we generate synthetic timeseries of damage by coupling a Poisson distribution to determine the number of passing ships per day, a vine-copula to quantify the multivariate joint distribution of the loading variables that define the primary wave height and a Bernoulli process and a bivariate copula to translate the primary wave height into the increment of damage. Afterwards, these damage curves are used to quantify a Gamma process. Thus, it is possible to conditionalize the joint distribution of the loading variables to generate the damage curves under different loading scenarios and evaluate the effects of these scenarios on the structure’s survivability. We exemplify the use of the methodology to assess the armor deterioration of a rock-armored groyne under ship-wave attack with and without a limitation in the speed velocity in the waterway.