Delay analysis in resource-constrained schedules

The schedule for construction delay analysis should consider resources because it is acknowledged that a schedule without resources is not realistic. However, the conventional resource-constrained scheduling (RCS) technique is not properly operated for the widely accepted delay analysis techniques such as the contemporaneous period analysis (CPA) and the “but-for” method. The “CPM + RCS” method for rescheduling to analyze delay impacts may cause unexpected activity sequence changes and the “RCS-only” method does not reflect the time impact of the duration reduction of an activity and may cause substantial project completion delay by a minor change in the activity duration. This study analyzes the problems that arise when CPA and the “but-for” method are performed on the basis of the conventional RCS technique and shows how the resource-constrained critical path method can be utilized in those delay analyses that have advantages as compared with the RCS technique.