Social network analysis for construction specialty trade interference and work plan reliability

Managing of multiple specialty trades working on a large number of interdependent tasks in complex construction projects can be challenging. There are various types of uncertainty associated with construction processes such as prerequisite work, weather, material and labor availability. One of the key uncertainty sources which have not been gained much attention is the specialty trades' (sub-contractors') interference in the construction jobsite during the project. Although the importance of controlling the trades' interference is acknowledged by the construction managers, applicable methods to visualize and analyze them numerically are limited. This paper uses social network analysis (SNA) to examine how the existing interference potential among the specialty trades is related to their work plan reliability (WPR) over the course of the project. It evaluates the consistency between the trades' WPR and the project network characteristics. A 28-week case study involving 43 specialty trades constructing of a single level, 50 million, 14,000 square meter data center was conducted. Primary results show that there is a moderate correlation between the plan percent complete (PPC) and centrality ratio and network density. The findings of this research can help project managers in managing the probable interferences among the working specialty trades and improving their WPR.