Buffer Sizing in CCPM Portfolios with Different Resource Capacities

Abstract

Although buffer sizing is one of the most investigated subjects in Critical Chain Project Management (CCPM), almost all the focus has been on its implications for single-project environments. Among the entire invented buffer sizing methods, the cut and paste method (C&PM) is the most accepted by practitioners and long-established CCPM software packages. This study concentrates on the use of C&PM in CCPM portfolios with different resource capacities with the aim of examining the performance of this method and identifying the most appropriate sizes of project and feeding buffers. This aim is pursued through considering ten different levels of resource capacity, conducting Monte Carlo simulations of randomly generated project data and comparing the results with deterministic duration values of the same portfolios with 30%, 40% and 50% buffer sizes. As a significant contribution, this study recommends what buffer sizes should be allotted in CCPM portfolios with different resource capacities.