Crashing construction projects considering schedule flexibility: an illustrative example

Time and cost are two of the most important performance indicators of construction projects. Project crashing is one of the effective methods for solving time-cost trade-off problems. However, in some instances, consuming all of the crash durations of the activities may lead to inflexible schedules. This paper proposes a project crashing model that aims to achieve more flexible schedules by means of assigning a crash duration consumption rate to each activity based on the preferred scheduling strategy. The applicability of the proposed model is presented along with an illustrative example. The Monte Carlo simulation is also performed to verify whether the proposed model is useful or not. The results revealed that the proposed model is an effective tool as it maintains schedule flexibility and increases the probability of completing the project in the targeted project duration. The proposed model also provides a new perspective for schedulers to solve project crashing problems.