Tradeoff Analysis of Offshore Structures Under Stochastic Excitation

Abstract

The analysis and design of structural systems such as offshore structures usually involve several design goals which are required to be maximized or minimized simultaneously. The design goals are in general potentially conflicting requirements reflecting technical and economical performances. The purpose of this work is to obtain in an efficient manner compromise designs that best represent the outcome that the designer considers potentially satisfactory. The designs are obtained by formulating a compromise programming problem, which is solved by an efficient first-order interior point algorithm. In order to exemplify the proposed methodology a typical offshore structural model is considered for analysis. The random sea is modeled as a Gaussian process following a Joint North Sea Wave Observation Project (JONSWAP) type spectrum for free surface elevation. Numerical results show that the proposed approach for decision making is quite effective.