برنامه ریزی و مدیریت حمل چند وجهی مواد خطرناک با انتخاب ظرفیت و ازدحام

• We study rail–truck intermodal transportation of hazmat with terminal congestion.• A nonlinear optimization model and a customized RTIM-heuristic are proposed.• Congestion at terminals could result in non-negligible hazmat risk.• Equipment service and utilization rates have a direct bearing on congestion risk.• Shorter delivery times would have a positive bearing on terminal risk.The current literature in the rail–truck intermodal transportation of hazardous materials (hazmat) domain ignores congestion at intermodal yards. We attempt to close that gap by proposing a bi-objective optimization framework for managing hazmat freight that not only considers congestion at intermodal yards, but also determines the appropriate equipment capacity. The proposed framework, i.e., a non-linear MIP and a multi-objective genetic algorithm based solution methodology, is applied to a realistic size problem instance from existing literature. Our analysis indicates that terminal congestion risk is a significant portion of the network risk; and, that policies and tools involving number of cranes, shorter maximum waiting times, and tighter delivery times could have a positive bearing on risk.