Study on the Governance of Opportunistic Behavior by Contractors in Subway Construction Based on SEM-SD

As a vital component of urban transportation systems, subways play a crucial role in the development of a city. However, opportunistic behaviors by subway construction contractors frequently occur, adversely affecting project objectives. This study employs literature review methods to identify six key dimensions that influence the governance of opportunistic behaviors by subway project contractors, thereby constructing a theoretical model of governance factors. Based on this theoretical framework, hypothesis testing and questionnaire design were conducted. Structural Equation Modeling (SEM) path analysis identified construction process management as the direct cause influencing the governance of opportunistic behavior by subway project contractors, exerting a direct effect on such governance. Meanwhile, industry standardization, external oversight mechanisms, project governance quality, contractor credit evaluation, and internal organizational controls within the construction firm were identified as indirect governance factors. A system dynamics model was employed for dynamic simulation analysis of the governance system, revealing the dynamic evolution of opportunistic behavior governance levels under various influencing factors. Scenario simulations identified the pathway, industry standardization → internal controls within the construction organization → project governance quality → construction process management → opportunistic behavior governance, as yielding the lowest frequency of opportunistic behavior occurrence and optimal governance levels. The findings provide a governance basis for addressing the frequent occurrence of opportunistic behavior in subway construction projects.