Multiobjective Optimization for the Planning of Prefabricated Bridge Construction Projects

A significant number of bridge construction projects utilize prefabricated elements to accelerate construction and reduce traffic disruptions while enhancing safety, quality, and sustainability. This study presents the development of a novel multiobjective model for optimizing the planning of prefabricated bridge construction projects. The model provides the capability of simultaneously maximizing safety, mobility, and sustainability while minimizing total construction costs. The model was developed in three main stages that focused on identifying decision variables, objective functions, and practical constraints; performing optimization computations using nondominated sorting genetic algorithm II (NSGA-II) along with four supporting modules; and evaluating its performance using a case study of prefabricated bridge projects. The model produces a Pareto front of near-optimal trade-off solutions across the four key objectives and generates detailed action reports that outline crew selection, scheduling, and logistics for each solution. The case study results highlight the model original contributions and its novel capabilities in quantifying and optimizing the impact of prefabricated bridge construction planning decisions on traffic mobility, work zone safety, sustainability, and total project costs including assembly, onsite storage, and transportation costs. These capabilities are expected to provide decision makers and bridge planners with much-needed support to make informed, data-driven decisions aligned with their project-specific priorities, leading to more efficient, sustainable, and cost-effective delivery of prefabricated bridge construction projects.