Adaptive Metamodel-Based Efficient Robust Design Optimization of Offshore Structure Under Wave Loading

The present paper deals with the Robust Design Optimization (RDO) of an offshore steel structure under wave loading considering parameter uncertainty. A novel Moving Least Squares Method (MLSM)-based metamodelling strategy has been adopted in the framework of MCS to evade extensive computational time requirement. The optimization problem is posed as weight minimization problem under displacement constraint. The proposed MLSM-based RDO strategy yields more accurate solutions than the conventional Least Squares Method (LSM)-based metamodelling when compared with the direct MCS results as benchmark. The proposed approach requires less computational time than the direct MCS. The results show that by compromising a small increment in structural weight, one can achieve robust and reliable design solution within affordable computational time by the proposed RDO approach.