A new approach on auxiliary vehicle assignment in capacitated location routing problem

Abstract

The location routing problem (LRP) considers locating depots and vehicle routing decisions simultaneously. In classic LRP the number of customers in each route depends on the capacity of the vehicle. In this paper a capacitated LRP model with auxiliary vehicle assignment is presented in which the length of each route is not restricted by main vehicle capacity. Two kinds of vehicles are considered: main vehicles with higher capacity and fixed cost and auxiliary vehicles with lower capacity and fixed cost. The auxiliary vehicles can be added to the transportation system as an alternative strategy to cover the capacity limitations and they are just used to transfer goods from depots to vehicles and cannot serve the customers by themselves. To show the applicability of the proposed model, some numerical examples derived from the well-known instances are used. Moreover the model has been solved by some meta-heuristics for large sized instances. The results show the efficiency of the proposed model and the solution approach, considering the classic model and the exact solution approach, respectively.

Keywords:

• location routing
• auxiliary vehicle
• capacitated
• simulated annealing

Additional information

Notes on contributors

Mahdi Bashiri

Mahdi Bashiri is an associate professor of industrial engineering at Shahed University. He received his BSc degree in industrial engineering from Iran University of Science and Technology. Also he got his MSc and PhD in the same field from the Tarbiat Modarres University. His research interest area includes the facilities planning and meta-heuristics.

Zeinab Rasoulinejad

Zeinab Rasoulinejad received her BSc degree from the Shahid Beheshti University of Iran in 2011. She received her MSc degree in industrial engineering from Shahed University of Iran. Her research is concentrated on development of routing problems in delivery networks.

Ehsan Fallahzade

Ehsan Fallahzade received his BSc and MSc degrees in industrial engineering from University of Bojnurd and Shahed University, respectively. His research interest includes operations research and transportation networks.