Jordan Journal of Civil Engineering

Simplified Solution of Time-Cost Trade-off Problem for Building Constructions by Linear Scheduling


�nder Halis Bettemir; Tugay Y�cel;


Time-cost trade-off is an important optimization problem for the contractors because its optimum solution minimizes the total project cost. Formation of the time-cost trade-off problem causes important workload since the problem requires preparation of different construction cost and duration alternatives of the activities. In this study, the formation of different construction alternatives are conducted by utilizing construction crew size and job efficiency curves derived from the literature. The composed construction alternatives of the construction items represent the construction cost and duration of the one story of high rise building. Precedence relationships of the main construction items are predefined and the construction schedule is formed by line of balance in terms of work days. The problem is optimized by genetic algorithm whose parameters are fine-tuned by experimental design. The developed approach is implemented on a spreadsheet application and the total optimization process is completed in an hour. This study contributes literature by proposing a systematic approach for the formation of construction alternatives of the time-cost trade-off problem. The proposed approach can be beneficial for the contractors and project managers to form and solve the time-cost trade-off problem.


time-cost trade-off, genetic algorithm, line of balance, optimization, experimental design