Fully probabilistic reliability and resilience analysis of coastal structures based on damage evolution simulation

Abstract

An integrated methodology is presented to ensure coastal structures’ resilience to extreme wave conditions i.e. their ability to withstand further wave actions without reaching their ultimate limit state. Specifically, a fully probabilistic reliability analysis of a rubble mound breakwater is performed here, in combination with a prediction analysis of the expected time of the structure’s maintenance. The methodology combines information on the joint probability density function of significant wave height, spectral peak wave period, and storms’ duration and calculates the probability of occurrence of different levels of damage in the structure’s lifetime via the use of a fully probabilistic reliability method. In this step, the breakwater’s armor element’s state is supposed to has a zero-damage level, before being exposed to each storm. Moreover, a resilience analysis is also described and applied by using the armor’s damage evolution model by Melby and Kobayashi (1998), estimating the expected year that the breakwater’s maintenance should take place. In this approach, the expected damage of the breakwater’s armour at the end of a storm is a function of the storm’s characteristics and the corresponding damage at the end of the previous storm. The methodology is applied to hindcast data at a location of the Barcelona coast in Spain. Thereby, an insight is gained for the extreme forcing on coastal structures induced by coastal storms, enabling the assessment of structure’s probability of failure and repair.