A new tabu search algorithm for the vehicle routing problem with backhauls

In the distribution of goods from a central depot to geographically dispersed customers it happens quite frequently that some customers, called linehauls, receive goods from that depot while others, named backhauls, send goods to it. This situation is described and studied by the vehicle routing problem with backhauls. In this paper we present a new tabu search algorithm that starting from pseudo-lower bounds was able to match almost all the best published solutions and to find many new best solutions, for a large set of benchmark problems.