TIME-COST TRADE-OFF SCHEDULING UNDER CONSTRUCTION LABOR RESOURCE CONSTRAINTS
Keywords:
Construction Scheduling, labor resource constraints, time-cost trade-off, multi-objective optimizationAbstract
Time and cost are the main goals of the construction project management. Planners are searching for the optimal schedules which give both early completion time and small total cost. The scheduling problem named Time-Cost Trade-off (TCT) is attended by previous research. From field surveys conducted in Thailand, contractors are also concerned about the fluctuation of labor resources supply. Most construction labor is seasonal workers who work in agriculture as well. This research, therefore, formulates the TCT model with labor resource constraints. Multi-objective goal programming and binary integer programming are used in the formulation. The mathematical expressions of this model are presented in the paper. Genetic Algorithms is used to search for optimal solutions. This new model is tested with the real data collected. The result shows that the scheduling model with labor resource constraints gives earlier project finish time and less project cost than the one without.
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