Risk assessment in construction schedules

Construction projects are initiated in complex and dynamic environments resulting in circumstances of high uncertainty and risk, which are compounded by demanding time constraints. This paper describes a systematic way to consider and quantify uncertainty in construction schedules. The system incorporates knowledge and experience acquired from many experts, project-specific information, decision analysis techniques, and a mathematical model to estimate the amount of risk in a construction schedule at the initiation of a project. The model provides the means for sensitivity analyses for different outcomes wherein the effect of critical and significant risk factors can be evaluated. The paper focuses on lessons learned from past projects and describes a risk assessment process involving typical inputs and expected outputs. The paper also briefly reviews the information technology of HyperCard and Excel, which were used to develop the system.