Removal of redundant relationships in an AON project network for evaluating schedule complexity

Since redundant relationships in an activity-on-node (AON) project network indicate that the schedule is more complex than it actually is, they should not be considered when evaluating the schedule complexity. However, identifying the relationships that can be removed while maintaining the project logic is not an easy task. For this purpose, this paper proposes a methodology, adapted from interpretive structural modeling, that basically transforms an AON project network into a network called minimum-edge diagraph which contains no redundant relationships. The methodology steps are explained through a demonstrative example of a simple hypothetical project. The application of the methodology to the AON network of a real construction project shows that it is easy to use yet effective in removing redundant relationships.