Discrete-event simulation (DES) of uncertainty-based time-cost trade-off analysis

Critical Path Method (CPM) is widely used in construction engineering scheduling. Through calculating Early Start (ES), Early Finish (EF), Late Start (LS), and Late Finish (LF), the duration of a project can be obtained, and critical path can be found. However, in reality, the duration of each activity is uncertain with a distribution, instead of a constant number. Meanwhile, the cost of each activity may vary when the duration of the activity changes, generating different Net Present Value (NPV). In this paper, a Discrete-Event Simulation (DES) methodology is introduced to deal with the uncertainty-based time-cost trade-off (TCT) analysis in construction scheduling problem. An example is stated to verify the proposed methodology.