Exploring the Effect of Interface Management on Project Success in Complex Capital Projects: The Moderating Role of Relational Capital

The recognition of the potential for interface management (IM) to enhance project success is widespread, both in academic literature and among industry professionals. The claim, however, lacks substantial empirical evidence to support its validity. Therefore, this study explored the relationship between IM and project success in complex capital projects from the perspective of relational capital. First, a comprehensive theoretical model is established to map the direct impact of IM on project success and the mediating role of relational capital. Second, based on a comprehensive literature review and in-depth expert interviews, a total of 152 questionnaire surveys on IM and project success were collected in China. The measurement of IM was conducted from three dimensions by correlation and factor analyses, namely, responsibility, time–space, and technical interface management. Finally, the partial least-squares structural equation modeling (PLS-SEM) technique was employed to empirically examine the positive impact of IM on project success and explore the moderating effect of relational capital. The results revealed that IM positively affects project success in complex capital projects, and this effect is achieved by fostering relationship capital among project stakeholders. The findings confirm that relational capital is an important perspective to understand how IM impact project success. The research provides a holistic understanding of the relationship between IM and project success, thus contributing to project management theoretically and practically.