Open AccessAssessing the Impact of the Lead/Lag Times on the Project Duration Estimates in Highway Construction
Author(s) -
Mohamed Abdel Raheem,
Jennifer McGee Reyes,
Xiaohui Wang,
Grecia Silva Sanchez,
Alyssa Marie Garza
Publication year - 2021
Publication title -
journal of architectural environment and structural engineering research
Language(s) - English
Resource type - Journals
ISSN - 2630-5232
DOI - 10.30564/jaeser.v4i3.3383
Subject(s) - lag , duration (music) , schedule , index (typography) , lead time , sensitivity (control systems) , scheduling (production processes) , lead (geology) , monte carlo method , criticality , time lag , environmental science , computer science , statistics , econometrics , operations research , engineering , operations management , mathematics , art , computer network , physics , literature , geomorphology , electronic engineering , world wide web , nuclear physics , geology , operating system
The literature mentions multiple factors that can affect the accuracy of estimating the project duration in highway construction, such as weather, location, and soil conditions. However, there are other factors that have not been explored, yet they can have significant impact on the accuracy of the project time estimate. Recently, TxDOT raised a concern regarding the importance of the proper estimating of the lead/lag times in project schedules. These lead/lag times are often determined based on the engineer’s experience. However, inaccurate estimates of the lead/lag time can result in unrealistic project durations. In order to investigate this claim, the study utilizes four time sensitivity measures (TSM), namely the Criticality Index (CI), Significance Index (SI), Cruciality Index (CRI), and the Schedule Sensitivity Index (SSI) to statistically analyze and draw conclusions regarding the impact of the lead/lag time estimates on the total duration in highway projects. An Excel-based scheduling software was developed with Monte Carlo simulation capabilities to calculate these TSM. The results from this paper show that the variability of some lead/lag times can significantly impact the accuracy of the estimated total project duration. It was concluded that the current practices used for estimating the lead/lag times are insufficient. As such, it is recommended to utilize more robust methods, such as the time sensitivity measures, to accurately estimate the lead/lad times in the projects scheduled.