Simulation and optimization for construction repetitive projects using promodel and simrunner

We introduce a new approach, called Relative Start and Idle Time (RSIT), to solve probabilistic scheduling problems of construction repetitive projects. RSIT is a process of determining a range of input variables and employing optimization through simulation to solve scheduling problems. RSIT reduces the modeler's effort because it does not heavily rely on manual trial-and-error. The two primary advantages of this approach are: (1) it does not require additional solving algorithm code and (2) it does not impose unnecessary limitations on the simulation model in order to solve the scheduling problem. The new approach is presented in detail and applied to a real past repetitive project of four four-story buildings. Results from RSIT are evaluated and compared to the results from a deterministic approach. The example is modeled in Pro-Model and optimized in SimRunner.