Route optimisation for winter maintenance

In many countries, winter maintenance is a requirement to keep public life going throughout the cold season. This paper investigates the optimization of salt spreading routes in Denmark in terms of service time and cost. It looks at salting as a capacitated arc routing problem and proposes a greedy randomized adaptive search procedure to this end. At the core of the proposed approach is a heuristic algorithm based on simulated annealing that improves the initial route by searching for alternatives within a predefined search space, taking into account a number of constraints and criteria at each iteration of the procedure. The performance of the optimization approach is tested on three different existing service routes, where it is shown to reduce route length by an average of 8.7% and service time by an average of 9.5%.