Journal of Scientific Research and Reports

Mega projects are often beset with cost escalations, delays in construction and increased operating and maintenance costs throughout their period of existence. Although both Building Information Modelling (BIM) and Digital Twins (DT) have shown promise to help reduce these obstacles individually, the combined use of the two technologies promises greater lifecycle cost optimisation. In this study, a systematic review of recent literature is undertaken to explore how the combination of BIM and DT through the use of conjoint techniques can help refine project delivery, reduce overruns, and simplify the process of maintenance in mega projects. The past decade of empirical and case-study studies is evaluated, and quantitative information about cost-saving, schedule-efficiency, maintenance cost-saving, and current challenges is mined. This study demonstrates that while BIM-DT integration can enable lifecycle cost savings of 20 to 40% through enhanced data integration and predictive maintenance, significant barriers to adoption persist. These include technical challenges in interoperability, high initial implementation costs, and organizational resistance to digital transformation. This study not only synthesizes current research but also offers a conceptual foundation for future empirical validation and practical application of BIM-DT integration in lifecycle cost management.