A Lagrangian relaxation approach for a machinery location problem in forest harvesting

The correct location of harvesting machinery is an important problem for the timber industry, as these are expensive pieces of equipment. Also, access roads need to be constructed within a season of harvesting. In this paper, we present the modelling of this problem as a mixed integer linear model which, without any special technique, is very difficult to solve. Strengthening of the original linear programming formulation, and a Lagrangian Relaxation algorithm are developed to improve the solution process. We show test results in a real industry problem.