Resource constrained project scheduling using simulation

Resource allocation is one of the most important issues of construction management. Two problems of resource allocation are of concern: resource levelling and resource scheduling. Traditionally, the resource scheduling problem is solved using either heuristic methods or optimization techniques. When heuristic methods are used, resource scheduling is treated as a subsequent problem for the CPM analysis. In this paper, the resource scheduling problem is handled using simulation, where logic dependence and resource availability limits are considered simultaneously during the time scheduling process. Simulation is applied to the resource scheduling problem at the project level. A simulation system called SIRBUS is used to schedule construction projects under resource constraints. Constant resource demand of activities is assumed, and the activity once started cannot be interrupted. Six example projects previously solved by different heuristic methods are re-solved using simulation. The results are compared with the latest heuristic models: current float technique and ranked positional weight method. In addition to the advantage that resource availability is considered during time scheduling as a starting point, which is an apparent feature of simulation, SIRBUS gives good results compared with existing heuristic methods.