Diagnose the Causes of Cost Deviation in Highway Construction Projects by Using Root Cause Analysis Techniques

The root cause analysis techniques are a good choice to be adopted to diagnose the root causes of cost deviation in highway projects. Many root cause analysis tools have emerged from the literature as generic standards for identifying root causes such as Fishbone diagram, Pareto diagram, and the 5-Why analysis. This study diagnosed twenty causes of cost deviation in highway projects in Republic of Iraq which they divided into three main groups (planning causes, designing causes, and execution causes). Pareto analysis showed that eleven causes out of twenty causes represent the most important causes of cost deviation, these eleven causes had been filtered by 5-Why analysis, this analysis concluded that the unavailability of enough information about the project is a root cause for planning causes group, while the clarity lack of the owner requirements is a root cause for designing causes group and finally, the poor efficiency of the administrative staff is a root cause for execution causes group.