Winter road maintenance operations require many complex strategic and operational planning decisions. The five primary problems involved in this intricate planning procedure include locating depots, designing sectors, routing service vehicles, scheduling vehicles, and configuring the vehicle fleet. The complexity involved in each of these decisions has resulted mainly in research that approaches each of the problems separately and sequentially, which can lead to isolated and suboptimal solutions. After discussing the complexity of the relaxed subproblems that would need to be solved to optimize the intricate winter maintenance operations, the research turns to a heuristic approach to more feasibly address the interrelated problems.
This report subsequently presents a systematic, heuristic-based optimization approach to integrate the winter road maintenance planning decisions for depot location, sector design, vehicle route design, vehicle scheduling, and fleet configuration. The approach presented is illustrated through an example of public sector winter road maintenance planning for a rural transportation network in Boone County, Missouri.
When applied to the real-world winter road maintenance planning problems for Boone County, the methodology delivered very promising results. The solution methodology successfully achieves the objective of a more integrated and less sequential approach to the problems considered. The integrated solution would allow the Missouri Department of Transportation (MoDOT) to maintain the same high level of service with significantly fewer resources. The results indicate that this methodology is a successful step towards solving realistic multiple-depot problems involving heterogeneous winter maintenance fleets.