A Branch&Cut algorithm for the Multi-Trip Vehicle Routing Problem with Time Windows

International audienceThe Vehicle Routing Problem with Time Windows (VRPTW) deals with the determinationof the trips of a homogeneous fleet of capacitated vehicles based at a central depot to deliver aset of customers, while complying delivery time intervals imposed by these latter. The MultiTripVRP with Time Windows (MTVRPTW) goes one step further by allowing vehicles toperform not one but a sequence of trips, called a journey, under a maximum overall shift lengthconstraint. Moreover, the time to load a vehicle is service-dependent, i.e. proportional to thetotal service time of the subsequent trip. Hence, the MTVRPTW consists in finding a set ofback-to-depot delivery trips and assigning them to vehicles so that the total travelled distanceis minimized and :Ieach customer is visited exactly once and service starts within the associated time window ;Ivehicle capacity is respected ;Itrips assigned to one vehicle do not overlap in time and do not exceed a maximum duration