Using greedy clustering method to solve capacitated location-routing problem

Abstract

This paper introduces a new heuristic method to solve the location-routing problem (LRP). Facility location problem (FLP) and vehicle routing problem (VRP) are considered simultaneously in the LRP. The problem selects the location of depot(s) to be established among a set of potential sites. On the other hand, the allocation of customers to depot(s), and the distribution routes between the customers and depot(s) are decided, too. In this paper, capacitated LRP (CLRP) is considered, in which the vehicles and the depots have a predefined capacity to serve the customers. A greedy clustering method (GCM-LRP) in four phases is proposed. The method clusters the customers using a greedy search algorithm, selects the most appropriate location of depot(s), allocates the clusters to the depot(s), and finally sets routes between the depot(s) and customers using ant colony system (ACS). The numerical experiments on a set of benchmark instances show the efficiency of the proposed method.