Cross-dock Door Assignment Problem: A New Linear Mixed Integer Programming Model

As a consolidation point for transported products, cross-docking not only reduces the total material handling costs, but also reduces the need to store the products in the warehouse. An appropriate assignment of supply and demand points to doors of the cross-dock would reduce the material handling costs in the cross-dock facility. Th is study addresses the cross-dock door assignment problem (CDAP) in which assignment of origins to strip (inbound) doors is done as well as assignment of destinations to stack (outbound) doors. Th e main purpose of this assignment is to minimize the total distance which is travelled by internal vehicles (e.g. forklifts) in the cross-dock facility. To formulate the problem, we develop a new linear mixed integer programming model. Th e model, then, is coded in LINGO software to determine the best assignment of origins and destinations to cross-dock doors. To show the applicability of the developed model, benchmark problems for the CDAP in the literature are solved.