Modeling stochastic project time–cost trade-offs with time-dependent activity durations

In real-life projects, both the trade-off between the project cost and the project completion time, and the uncertainty of the environment are considerable aspects for decision-makers. Moreover, in some projects, activity durations show their complexity with time-dependence as well as randomness. In this paper, a stochastic time-dependent time–cost trade-off problem is introduced. To meet different management requirements, three stochastic time–cost trade-off models are built. The proposed models are dealt with an intelligent algorithm combining stochastic simulations and genetic algorithm, where stochastic simulation technique is employed to estimate random functions and genetic algorithm is designed to search optimal schedules under different decision-making criteria. Finally, some numerical experiments are given to illustrate the algorithm effectiveness.