Robust resource-constrained project scheduling problem of the project's subcontractors in a cooperative environment under uncertainty: Social complex construction case study

Improvement of project scheduling is a complicated task due to numerous activities and various resources. Accordingly, the resource-constrained project scheduling problem (RCPSP) is an NP-hard problem that minimizes the time and cost of the project. In this paper, the goal is to model the problem under uncertainty in the availability of the resources and activities duration simultaneously. Subcontractors of the construction projects are motivated to form a coalition to reduce the makespan, increase the availability of the resources and maximize their profits. Initially, the robust optimization (RO) model is developed for the RCPSP based on the multi objective optimization method in which the uncertainty is modeled in a set of scenarios. The behavior of subcontractors is considered by supper-additivity in cooperation, satisfaction level and stability of coalitions. The results of the proposed model demonstrate that the subcontractors can work together in a coalition and obtain more profit rather than working individually. Then, game theory methods such as Shapley Value, Max-Min core, and Equal Profit Method are applied to fairly allocate excess profit of the coalition.