Identification of critical paths leading to cost claims for underground metro projects: a system dynamics approach

Purpose Infrastructure projects play a vital role in the development of countries' economies. However, these projects, notably underground ones, are encountering growing claims as they are subject to many unknowns. Without having a clear insight into the causes of claims and their influence on one another, it is not possible to mitigate their adverse impacts on these projects' goals. To this aim, the main purpose of this study is to identify the critical paths leading to cost claims for underground metro projects. Design/methodology/approach First, causes of claims were identified through a literature review and then refined to 22 main causes according to the opinions of 148 Iranian experts. A qualitative system dynamics (SD) model was then provided to visualize how various causes interact with each other. The model was developed and validated by drawing on the expertise of industry-related experts, and the critical paths were finally recognized based on their frequency and severity indexes. Findings The findings revealed that each cause should be evaluated based on their connections with others as there are complex relations among the causes. It was also shown that the major claim paths among others were initiated due to ambiguous contract clauses, unforeseen physical conditions and land handover problems. Originality/value The findings of this study provide a better insight into how various causes of claims for underground metro projects are related to each other and can eventually assist project managers of different parties, even in other countries, to select proportional strategies to mitigate their adverse impacts.