Benefit analysis of shared depot resources for multi-depot vehicle routing problem with fuel consumption

Shared depot resources, which allow the route of a vehicle to start from a depot and end at any one of the depot sets, can potentially reduce delivery distance and fuel consumption because more choices are provided for route arrangement. To quantify the benefit, we define the benefit ratio between unshared and shared depots and prove that the maximum benefit ratios on route distance and fuel consumption are up to 2. Then the factors that affect the benefit ratio are analyzed by computational experiments. Computational results show that the benefit of shared depot resources depends on instance characteristics. Three characteristics are found to be significant to the relative performance, namely, depot-customer geographic distribution, maximum route distance, and number of depots.