Graphical Delay Tracking for Linear and Repetitive Schedules

Abstract

Construction project delays can stem from a myriad of factors and pose significant challenges for owners and contractors. While numerous methods for analyzing delays exist, the majority are designed for network scheduling, lack contemporaneous tracking (i.e., do not allow for identifying and tracking delays as they occur), and struggle with attributing delays to specific stakeholders. Therefore, this paper introduces a novel graphical approach to monitor delays by comparing as-planned and as-built schedules at the activity level. Distinguished by its contemporaneous nature, the new method allows real-time tracking and quantification of delays. This facilitates identifying their origin and potential causes. Rules for constructing the graphs of various delay scenarios are demonstrated for typical activity combinations. The effectiveness of the proposed method is validated via a case study that showcases its practical application. Implementing it is straightforward, and while the method could be applied to network schedules, its relevance lies in linear and repetitive schedules. The cyclic nature of tasks in such schedules underscores the importance of contemporaneous delay tracking to facilitate swift remedial actions and pinpoint liability. In this study, the authors present a new way to track delay using graphs by comparing starts, productivities, and finishes of as-planned and as-built schedules at the activity level. Because it is contemporaneous, the new approach tracks and measures delays in real time, currently manually, but easily implemented as computer code. This method makes it easier to find the source and possible causes of activity and project delays. Detailed rules are derived for common activity scenarios and interactions on how to create the respective graphs. A real-world study demonstrates how the proposed method can be used to substantiate its potential value to practitioners in industry. The proposed approach is practical, and while it could be used for network schedules, it is especially useful for linear and repetitive schedules.