Slip chart-inspired project schedule diagramming: Links, extension to network schedules, and unification

Schedule delays are an unfortunate prevalent occurrence in the construction industry. To clearly visualize, track, and mitigate them, graphical and analytical tools are needed. But traditional bar charts do not clearly show delays, and network charts all but hide them. Neither facilitates side-by-side comparisons of schedule updates. Networks can be converted into a modified slip chart from the aerospace industry, which is particularly adept at analyzing delays. Contributions to the body of knowledge include the ability to communicate schedule information more efficiently with less ink, yet in a time-scaled manner, including lead or lag constraints, performing side-by-side comparisons that immediately reveal float gain or loss versus criticality, rapidly identifying underperforming activities, and scrutinizing delay events and assigning responsibility to project participants. To validate the new approach, a delay example from the literature is reanalyzed to gain insights into schedule performance. Comparing the network conversion with a previously developed linear schedule one indicates that the entire approach provides a single framework to plan and control project schedules, which thus can be called the Unified Diagramming Method.