The management of complexity and scheduling in mega-construction projects is a persistent challenge due to their vast scope and inherent intricacies. This study explores the application of the Functional Resonance Analysis Method (FRAM) in construction project management, focusing particularly on its utility for large-scale projects. Through an extensive literature review, a notable gap was identified in the application of FRAM throughout the entire lifecycle of mega projects. To address this, the study proposes an innovative model that integrates FRAM with the Project Management Body of Knowledge (PMBOK) process groups and enhances it using the Analytic Hierarchy Process (AHP) across all knowledge areas. This model is exemplified through a Channel Tunnel project case study, demonstrating FRAM’s ability to dissect complexities, highlight critical factors, and sequence activities effectively. Our findings illuminate the nuanced interdependencies within the Channel Tunnel project and showcase the efficacy of the FRAM model in enhancing project visibility, decision-making, and overall management. By promoting the integration of FRAM, this study contributes a novel perspective to project management, advocating for a more resilient and adaptive approach to managing the challenges of mega-construction projects.