Pareto front generation for bridge deck management system using bi-objective optimization

Abstract

Bi-objective Optimization (BOO) method for the allocation of bridge deck Maintenance, Repair, and Rehabilitation (MR&R) budget is proposed using Bridge Management System (BMS) models. BOO problem is usually solved by using weighted sum method due to simple and easy of application. However, it is generally known that weighted sum method with linear objective functions finds the optimum solution which always lies on the boundary of feasible region. This phenomenon doesn't help the bridge engineers to have the choices when trade-off has to be made between objectives. Moreover, evenly distributed weights on objective functions does not guarantee the uniform distribution of optimized solution sets. This paper compares several multi-objective optimization techniques and proposes the improved solution technique that can be competent in terms of applicability for non-convex problem as well as production of only Pareto optimal solution sets. The proposed optimization technique is based on modification of well recognized method of “Normal Boundary Intersection” by Das and Dennis (1998). Using bi-objective optimization technique on bridge MR&R, decision maker will have more choice for the allocation of budget. Data obtained from Wyoming Department of Transportation (WYDOT) are used to validate the feasibility of application of proposed method for the maintenance of bridge decks.