Optimization of float use in risk analysis-based network scheduling

Abstract Floats are often used in project networks for resource allocations and as an alternative for reducing project costs without causing negative impact on project duration. However, when the time uncertainties of non-critical activities are great, the use of floats can lead to an increased risk of project schedule overruns, and accordingly an increase in project costs. This paper presents a procedure to optimize the use of floats in a project network. This procedure integrates schedule risk analysis and cost risk analysis. The changes in project costs, associated with the impact of the use of floats on the duration of the project, are calculated. Accordingly, the optimum use of the floats is identified. An application optimizing the use of floats in a bridge project is presented to illustrate the procedure.