Reliability-Based Multiobjective Design Optimization of Reinforced Concrete Bridges Considering Corrosion Effect

Chloride-induced corrosion is known as the dominant cause of premature damage in reinforced concrete (RC) bridges in the United States. However, the current corrosion management strategies do not suggest an optimum design procedure for RC bridges in corrosive environments considering both reliability and cost. In this paper, a module based on a reliability-based multiobjective design optimization (RB-MODO) technique using a nondominated sorting genetic algorithm is proposed for the optimum design of RC bridge beams considering corrosion. The procedure simultaneously maximizes the reliability of the structure and minimizes the material costs, given a design service life. As an illustration, the developed procedure is used for flexural design of interior T beams of a RC bridge with and without considering corrosion effect subjected to various design constraints and service lives. Three types of materials are used in the design process: normal strength concrete with black steel rebars, normal strength concrete with epoxy-coated rebars, and high-performance concrete with black steel rebars. Lastly, the optimum design strategy is selected among the considered materials based on the Pareto front results obtained from the proposed RB-MODO procedure