Probabilistic Optimal Design of Rubble-Mound Breakwater

Abstract

The present paper focuses on a methodology for the optimal design of a rubble-mound breakwater using a probabilistic analysis. In this (optimization) problem formulation, the total construction cost is minimized, subject to the constraints related to geometry, safety margins in different failure modes (overtopping armor instability failure, toe erosion, and settlement failure), and acceptable yearly failure rate (a value indicating chance of failure). The aforementioned method is illustrated by its application to the design of a multilayer rubble-mound breakwater that is under construction at Thalai Fishing Harbour, Thalassery, Kerala, India. Then the derived optimal design is compared with the results of conventional design. The comparative study reveals that the proposed probabilistic design resulted in a better economical design.