# Digital Twin Framework for Road Infrastructure Management
## 7 Discussion and Conclusions
In most cases, standards should be adaptable to specific situations, accommodating the particular needs of stakeholders and users. Similarly, not all features presented in this study, particularly the functional elements within the data analytics/application layer, must be implemented. Thus, only features relevant to a specific use case should be adopted, as this study primarily aims to demonstrate the overall functional scope identified through the literature review. Overall, this study contributes to the development of a DT framework for road infrastructure management, addresses emerging needs in the sector, and offers insights for the future development of standards in both the built environment and the AEC industry. Furthermore, researchers and practitioners can use this study as reference material, similar to a concise reference model dictionary or thesaurus, when selecting or comparing implementation frameworks and models. This study is limited to a few selected papers (a total of 26) in the road infrastructure management domain. Future studies could undertake a more comprehensive and expanded review, incorporating all of the relevant literature in this domain. Additionally, future developments may include collecting opinions and evidence from practitioners, researchers, and industries to improve relevance and findings. Such efforts could contribute to the development of a knowledge repository or organizational system, where various layers with similar features or meanings can be automatically generalized or integrated based on their semantics. Thus, all of these are essential for further developing an inclusive DT framework for city-level integration and the management of road assets and for delivering requirements in the domain to support future standardization efforts. Moreover, this study introduced a conceptual DT framework for road infrastructure management that needs to be implemented in real-world scenarios to test its functionality and adaptability. We presented one potential implementation case focusing on bridge management, and we anticipate that more in-depth insights will emerge after a practical implementation. Additionally, other asset management areas, such as road pavement or tunnel management, should also be considered. Furthermore, there is potential to extend this framework to multimodal transportation networks, including railways, waterways, and possibly airways, to create an ecosystem of interconnected DTs. Future studies can build on the proposed framework to address these challenges. Lastly, as the application areas expand, issues related to scalability, such as handling big data, computational performance, and network security, must also be addressed. Conceptualization, methodology, investigation, data curation, writing--original draft preparation, M.B. ; writing--review and editing, M.B., S.S. and W.L. ; visualization, M.B. ; project administration, M.B. and S.S.; funding acquisition, W.L. All authors have read and agreed to the published version of the manuscript. This research was supported by the National Research Foundation of Korea (RS-2021-NR060108), the Korea Institute of Energy Technology Evaluation and Planning (KETEP), and the Ministry of Trade, Industry, and Energy (MOTIE) of the Republic of Korea (No. RS-2022-KP002719). Not applicable. Data Availability Statement: Data are contained within the article. The authors declare no conflicts of interest.