Multi-Project Multi-Resource Leveling Using Mixed Integer Programming

In construction projects, resource leveling aims to provide efficient resource planning during project implementation by reducing possible fluctuations in resource usage. Decision makers mostly focus on the single project to optimize its resource usage by applying various objective functions of resource leveling problem. However, in real life, multiple projects may be performed in the same time period. Hence, leveling the resources of each project separately generates sub-optimal solutions since interactions between projects due to common resource usages are ignored. Therefore, the projects with shared resources should be leveled together to reach the global optimum solution. In this study, an optimization model is developed using Mixed Integer Programming (MIP) to minimize peak usage of multiple types of trades in multiple construction projects. Performance of the model is tested with two 300-activity construction projects and three different resource trades. The results show that MIP model offers the optimal solution to the tested multi-project multi-resource leveling problem