Caseplan: A case-based planner and scheduler for construction using product modeling

Construction planning and scheduling are important to contractors for estimating the cost and duration of a project they are to bid on and construct. Many projects specify incentive and disincentive clauses for completing projects early and late. The timely completion and success of a project rely on good planning and scheduling. Contractors who repeatedly build the same kind of facilities acquire experience in scheduling the needed construction work. When parts of a facility's design are copied from one project to the next, the previously developed schedules could possibly be reused to schedule future work. This dissertation presents a construction planner and scheduler, named CasePlan, that automates the planning and scheduling process through the use of experience encoded in cases. CasePlan enables a contractor to specify a facility design using a product model, describe the relationships between product components and parts of a schedule (e.g., activity subnetworks, construction crews), and store this information as a case. As a decision support tool, CasePlan enables the contractor to search for cases whose facility designs are similar to that of a new project. The similarity assessment is based on the relative importance values that the contractor assigns to the components and their attributes in the product model. As an automation tool, CasePlan creates the schedule of a new project by reusing parts of the schedules whose associated designs are most similar to that project's design. The result is a schedule in which construction alternatives are chosen from those used in previous cases based on the new project scheduling constraints. The contractor/system-user can interact with CasePlan during its operation or modify the resulting schedule to add detail needed for executing the schedule in the field. Two types of construction projects have been studied for the development of CasePlan. One is the Kit-of-Parts post offices, in which designs are made by reusing design modules defined as Parts. The other is the boiler erection for fossil-fueled power plants, in which the design process is standardized and component configurations are similar across designs. These projects were chosen because their schedules are similar within each project type, which suggested that practitioners had a high incentive and were likely to reuse schedules. CasePlan's similarity assessment for boiler erection projects was validated using a survey. CasePlan's schedules and usability were subjectively evaluated also by the interviewed professionals.