Activity vulnerability index for delay risk forecasting

The vulnerability of construction activities to delay factors controls the magnitude of the delay impact. Vulnerability characteristics of construction activities result in different patterns of duration variation. To identify the relationship between the delay factors and an activity's vulnerability, an activity vulnerability index was developed based on the subjective knowledge of experienced experts in construction operations. Incorporating the fuzzy set theory, the index provides not only information about the quantified vulnerability characteristics of an activity but also a reference for an activity criticality assessment. This study intends to suggest a framework for delay risk assessment and forecasting.