Development of an ant colony optimisation-based heuristic for a location-routing problem in a two-stage supply chain

The location-routing problem (LRP) considers facility-location and vehicle-routing decisions. These decisions have to be tackled simultaneously since they are interdependent. In this work, a two-stage LRP is considered wherein customers are to be served from a number of plants through a number of depots. Since LRP is an NP-hard problem, heuristic approach becomes the only alternative to solve the problem as the problem size increases. An ant colony optimisation (ACO)-based heuristic is proposed to solve the problem. For the purpose of performance evaluation of the proposed heuristic, various problem sizes are generated and the computational results are analysed. The results of this study reveal that the proposed heuristic is efficient for solving location routing problem in a two stage supply chain.