A Critical Investigation on Causes, Effects, and Solutions of Delay and Cost Overruns in Deep Excavation Projects – a Case Study for Iran

The considerable need for construction in congested urban areas necessitates deep excavations, and such projects suffer significantly from delay and cost overruns. There is, therefore, a limited perspective on this in various soil stabilisation methods. Through a case study for Iran, this paper aims to identify the dominant causes of delay and cost overruns in two common stabilisation methods, the bracing strut/truss retaining structure and the top-down construction, The results of the analysis were illustrated using cause-and-effect diagrams. The findings show that the contractor plays the most significant role in delay and cost overruns