Risk assessment in construction schedules

Construction projects are initiated in complex and dynamic environments res ulting in circumstances of high uncertainty and risk, which are compounded by demanding time constraints. This paper describes a systematic way to con sider and quantify uncertainty in construction schedules. The system incorp orates knowledge and experience acquired from many experts, project-specifi c information, decision analysis techniques, and a mathematical model to es timate the amount of risk in a construction schedule at the initiation of a project The model provides the means for sensitivity analyses for differen t outcomes wherein the effect of critical and significant risk factors can be evaluated. The paper focuses on lessons learned from past projects and d escribes a risk assessment process involving typical inputs and expected ou tputs. The paper also briefly reviews the information technology of HyperCa rd and Excel, which were used to develop the system.