Resource-Based Exploratory Analysis of Project Complexity Impact on Phase-Based Cost Performance Behavior

In the field of construction engineering, practitioners frequently encounter uncertainties in the process of decision-making and management of complex projects. These uncertainties associated with project complexity, which vastly affect the project development and execution process, may cause favorable/unfavorable impacts on projects cost performance. Several scholars believe that project complexity may cause unintended consequences on project performance; however, some other researchers stated that complex projects might receive higher attention and more resources and as a result, may face less cost overruns. Therefore, this study initially aims investigate the impact of complexity on phase-based cost performance. For this reason, 44 case studies consisting 30 high complexity projects and 14 low complexity ones were collected. Then, engineering, procurement and construction (EPC) phase cost performance of high and low complexity projects were studied and compared. To analyze the collected data, two-sample t-test was utilized. Analysis indicated that complex projects have better EPC phase cost performance compared to low complexity ones. Finally, to find out the underlying causes of better cost performance of high complexity projects in comparison with low complexity ones, the allocated resources and implemented best practices (BPs) were studied. It was observed that high-level of constructability, alignment, partnering, front-end planning, team building, and change management best practices were implemented in complex projects. The findings of this study can help project/program managers (PM) to better understand the phase-based behavior of cost performance in complex projects, and hence implement strategies and allocate resources effectively and efficiently in complex projects.