Progress-based construction scheduling

A new construction scheduling technique, developed on the basis of progress charts and Gantt (bar) charts, is presented. The main aim of the development is to overcome the problem of fragmentation of activities during the application of the conventional critical path and precedence diagramming methods to construction projects. However, the level of detail available in these methods for the representation of precedence relationships has been preserved and extended. Timing relations are defined among any events in activities instead of the start and end only; these relations may be multiple and expressed in terms of progress level. The concepts of activity timing and scheduling and project timing are elaborated, starting from definitions of temporal constraints for single activities and proceeding through timing relations. The concepts of slacks, free slacks, and criticality are defined and discussed in detail. The process of project timing, project scheduling, updating, and slack computation are illustrated numerically on a small sample project.