Quantification of spatial temporal congestion in four-dimensional computer-aided design

This paper further develops the models proposed by prior research in the field of workspace conflict using four-dimensional computer-aided design. The approach developed here analyzes spatial demand and supply from the perspective of construction operators, and a modeling methodology based on spatiotemporal utilization is proposed. The utilization factor model is developed to show that the criticality of the operator's spatiotemporal demand leads to worksite congestion and that congestion is a form of worksite conflict. The interference of other space entities increases the space demand, and this increment is quantified with a "dynamic space interference" index This indicator is developed to identify activity spaces which suffer congestion. A decision making tool, the "congestion penalty indicator," is developed which obtains a schedule-level value for analysis, evaluation, and comparison. Finally, a case study on the refurbishment of an oil refinery column is used to demonstrate the application of the above concepts in successfully identifying a better schedule with respect to on-site congestion.