Enhanced But-For Method to Apportion Net Delays and Accelerations
Publication: Journal of Construction Engineering and Management
Volume 147, Issue 7
Abstract
The but-for analysis and its improved modifications have been proposed in the literature to provide a systematic methodology to analyze project delays and accordingly determine the parties’ contribution in a manner that does not depend on any party’s viewpoint. These methods, however, only apportion net project delays, overlooking net project accelerations that can be owner requested or voluntarily done by the contractor. This technical note thus aims at extending the but-for computations to apportion net schedule accelerations. The proposed enhanced but-for method (EBFM) uses Venn diagrams and set theorem to represent all concurrent delays/accelerations that are shared among the three project parties: owner, contractor, and third party. Accordingly, a mathematical formulation has been proposed to compute each party’s contribution to net project delays and/or accelerations. A case study is used to demonstrate the EBFM method and prove its usefulness to both researchers and practitioners. EBFM offers a computational approach to help prepare and settle claim disputes in a fair and repeatable way, considering a variety of project conditions that include delays and accelerations.
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Data Availability Statement
All data generated or analyzed during the study are included in the published paper.
References
AACE (American Association of Cost Engineers). 2011. Forensic schedule analysis. AACE Recommended Practice 29R-03. Fairmont, WV: AACE.
Arditi, D., and T. Pattanakitchamroon. 2006. “Selecting a delay analysis method in resolving construction claims.” Int. J. Proj. Manage. 24 (2): 145–155. https://doi.org/10.1016/j.ijproman.2005.08.005.
Bhih, M., and T. Hegazy. 2020. “Improving concurrency assessment and resolving misconceptions about the but-for delay analysis technique.” J. Leg. Aff. Dispute Resolut. Eng. Constr. 12 (2): 1–10. https://doi.org/10.1061/(ASCE)LA.1943-4170.0000378.
El-adaway, I. H., S. A. Fawzy, R. Bingham, P. Clark, and T. Tidwell. 2014. “Different delay analysis techniques applied to the American Institute of Architects A201-2007 standard form of contract.” J. Leg. Aff. Dispute Resolut. Eng. Constr. 6 (3): 02514001. https://doi.org/10.1061/(ASCE)LA.1943-4170.0000145.
Fawzy, S. A., and I. H. El-adaway. 2013. “Contract administration guidelines for effectively and efficiently applying different delay analysis techniques under World Bank–funded projects.” J. Leg. Aff. Dispute Resolut. Eng. Constr. 5 (1): 35–44. https://doi.org/10.1061/(ASCE)LA.1943-4170.0000104.
Mbabazi, A., T. Hegazy, and F. Saccomanno. 2005. “Modified but-for method for delay analysis.” J. Constr. Eng. Manage. 131 (10): 1142–1144. https://doi.org/10.1061/(ASCE)0733-9364(2005)131:10(1142).
Menesi, W. 2007. “Construction delay analysis under multiple baseline updates.” Master’s thesis, Dept. of Civil and Environmental Engineering, Univ. of Waterloo.
SCL (Society of Construction Law). 2002. Delay and disruption protocol. Wantage, UK: SCL.
Yang, J.-B., and C.-K. Kao. 2009. “Review of delay analysis methods: A process-based comparison.” Open Constr. Build. Technol. J. 3 (1): 81–89. https://doi.org/10.2174/1874836800903010081.
Yang, J.-B., and P.-C. Yin. 2009. “Isolated collapsed but-for delay analysis methodology.” J. Constr. Eng. Manage. 135 (7): 570–578. https://doi.org/10.1061/(ASCE)CO.1943-7862.0000016.
Zack, J. 2001. “But-for schedules—Analysis and defense.” Cost Eng. 43 (8): 13–17.
Zhang, K., and T. Hegazy. 2005. “Apportioning concurrent delays and accelerations using daily windows.” In Proc., Congress: Construction Research Congress 2005: Broadening Perspectives, edited by I. D. Tommelein, 787–796. Reston, VA: ASCE. https://doi.org/10.1061/40754(183)77.
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Information
Published In
Journal of Construction Engineering and Management
Volume 147 • Issue 7 • July 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Sep 1, 2020
Accepted: Feb 3, 2021
Published online: Apr 28, 2021
Published in print: Jul 1, 2021
Discussion open until: Sep 28, 2021
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