A mixed integer model for optimization of discrete time cost tradeoff problem

Tatar, Ali Can
Bilir, Mert
Sönmez, Rifat
Atan, Sabri Tankut
In construction projects, activity durations can be expedited by allocating additional resources. Decreasing activity durations by means of crashing, usually leads to increase in the direct expenses. This trade-off between time and cost is called as the time-cost trade-off problem. Since in practice many resources are available in discrete units, numerous research has focussed on the discrete version of this problem called the discrete time-cost trade-off problem (DTCTP). Achieving the project schedule that satisfies the project requirements at an optimum cost is crucial for effective scheduling and management of construction projects. Despite the importance of DTCTP, very few research focused on generating and solving of large scale instances. The objective of this proceeding is to generate large scale instances that reflect the size of real-life construction projects and to solve these instances using mixed integer programming method (MIP) to enable a benchmark set with optimal solutions. Within this context, large scale instances that reflect the size of real-life-size construction projects are generated. A MIP model is developed and the majority of the instances is solved to optimal using GUROBI optimizer.
Creative Construction Conference (2016)


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Citation Formats
A. C. Tatar, M. Bilir, R. Sönmez, and S. T. Atan, “A mixed integer model for optimization of discrete time cost tradeoff problem,” Budapest, Hungary, 2016, vol. 1, p. 478, Accessed: 00, 2021. [Online]. Available: http://2016.creative-construction-conference.com/wp-content/uploads/2016/06/CCC2016_Proceedings.pdf.