The multi-objective reliability-based design optimization for structure based on probability and ellipsoidal convex hybrid model

•A new multi-objective reliability-based design optimization method is proposed.•A two-layer nested optimization problem is obtained based on decoupling strategy.•The IP-GA and μMOGA are employed as inner and outer layer optimization operator.•The fine optimization results exhibit the applicability of the present method. A multi-objective reliability-based design optimization method is proposed based on probabilistic and ellipsoidal convex hybrid model. With reliability index as the constraint, a three-layer nested multi-objective optimization problem is involved. To reduce the computation costs, an efficient decoupling strategy is presented to transform the original problem into a two-layer nested optimization problem. Then the intergeneration projection genetic algorithm and the micro multi-objective genetic algorithm are employed as inner and outer layer optimization operator to solve the multi-objective optimization problem, respectively. Finally, the present method is applied to three numerical examples and the results demonstrate the effectiveness of the present method.