Simulation-based planning for construction

Construction projects are characterized by the random nature of the conditions under which they are implemented and by the dynamic utilization of resources. Since site conditions vary randomly and resources are dynamically utilized on various work tasks, planning of construction projects using traditional tools like critical path method (CPM) becomes limited and induces deficiency in the resulting plan. This research demonstrates that a simulation based methodology is appropriate to model such a scenario. Hierarchical Simulation Modeling (HSM) method, a simulation based method, for planning of construction projects is developed in this work. HSM utilizes the concept of "hierarchy" of work involved on a construction project. Under this concept a project is divided into operations, processes and work tasks. A resource library for the project is created after the creation of the work breakdown structure (WBS). Then based on the construction logic various operations are sequenced using serial, parallel, cyclic and hammock links. Process models are then developed using the CYCLONE method. Enhancements have been made to the CYCLONE elements to accomplish simultaneous simulation of processes using common resource pools. This includes addition of resource manipulation elements and process inter-linkage. The final step in HSM analysis is to extend all the models to a common level where simulation takes place. Planning of a bridge project (Peace River bridge) was performed using HSM to illustrate HSM concepts and its advantages. It was demonstrated that HSM will prove to be an efficient tool for project planning. The key factors for this efficiency originate from the fact that the method allows demarcation of project information into logical and manageable packages, is driven by allocation and utilization of resources, and allows advanced facilities such as cycling of operations and reusable modular model components.