A two-stage packing procedure for a Portuguese trading company

Abstract

This case study deals with a two-stage packing problem that has to be solved in the daily distribution process of a Portuguese trading company. At the first stage boxes including goods are to be packed on pallets while at the second stage these pallets are loaded into one or more trucks. The boxes have to be transported to different customers and the actual goal is to guarantee a sufficient utilization of the truck loading spaces. A two-stage packing procedure is proposed to cover both problem stages. First boxes are loaded onto pallets using a well-known container loading algorithm. Then trucks are filled with loaded pallets by means of a new tree search algorithm. The applicability and performance of the two-stage approach was evaluated with a set of instances that are based on actual company data.