A Comprehensive Categorization and Flowcharting for Schedule Delay Analysis Methods

Abstract

A bewildering array of over two dozen delay analysis methods exists from which construction professionals may choose. However, no comprehensive comparison and synthesis have been made for all such methods as to their required inputs, structured processes, and outputs. ASCE Standard 67-16 does not specify any particular retrospective or contemporaneous analysis method. Moreover, while many methods are related, differences between versions have remained unclear. Methods may also follow the same process but be given different names in the literature. This study, therefore, synthesizes 26 delay analysis methods. Each algorithm is formalized via a verified process into a flowchart that structures its input, process, and output. Based on this, capabilities and shortcomings can be identified. Subsequently, the connections between methods are studied and compiled into a family tree based on their timing view (i.e., contemporaneous or retrospective) and calculation direction (i.e., as-built to or from as-planned).