Locating mobile facilities in railway construction management

• We introduce a location problem with mobile facilities, motivated by a railway construction project.
• We present mathematical formulations of the problem and adapt the formulations to the similar problems in the literature.
• We propose a preprocessing heuristic in order to find good solutions to large-sized problems in reasonably short times.
• Computational performances of formulations and heuristic are illustrated on a set of test instances.
• Our suggested solution to the case study problem results in 10% reduction in the current total cost.

The location problem with mobile facilities is motivated by a real-life railway construction project. In railway construction, (im)mobile concrete batching facilities are located to build viaducts and tunnels on a line over a planning horizon. The problem is to determine the number and types of facilities to be located, to schedule the movement of mobile facilities, and to make concrete production-allocation decisions, so that all requirements are satisfied, facility capacities are not violated, and the total cost is minimized. To the best of our knowledge, such a problem has not been studied in the literature before. Two mathematical models and a preprocessing heuristic are developed to solve the problem. Computational results on the real case study problem and randomly generated test problem instances show that locational decisions are important in construction management.