A simulation model for resource constrained scheduling of multiple projects

Since the late 1950's, Critical Path Method (CPM) and Programme Evaluation and Review Technique (PERT) have been widely used in the construction industry for planning and scheduling construction projects. The major drawback of these two techniques is the assumption of unlimited resource availability. In many real life situations, construction projects must be scheduled under limited resources. The problem becomes more and more complex when the resources are allocated and shared among multiple projects. This challenge of allocating scarce resources to the competing activities of different projects is of great concern to any project manager. Such decisions need to be made quickly. The availability of a decision rule or heuristic, which will be effective in minimising the total project tardiness, can be especially valuable. A simulation model has been developed to schedule the activities in the multiple projects when the resources are highly constrained.