## 5 Conclusions  
Digital twins enable the simulation of various scenarios that may arise in their physical counterparts, facilitating the exploration and analysis of management tasks. This capability enhances decision-making processes by enabling the anticipation of potential outcomes. However, many existing 3D digital city models lack a complete virtual library, largely due to the absence of the parameters or attributes provided by BIM models. To advance technological development in digitization, this research proposes a comprehensive methodological process for integrating GIS-3D and BIM digital models. The goal of this integration is to achieve effective interoperability between the two platforms, using tools compatible with computerized maintenance management systems (CMMSs). This integration leverages advanced 3D navigation within the built environment, allowing stakeholders to interact \begin{table}
\begin{tabular}{l c c} \hline \hline \multirow{2}{*}{**Topic**} & \multicolumn{2}{c}{**Savings (\%)**} \\  & **Time** & **Other Resources * \\ \hline Cost of CMMS software license & - & \(\approx\)50 \\ \hline Management of documentation & 90–95 & 80–90 \\ generated throughout the life cycle & 75–80 & 70–80 \\ \hline Management of corrective maintenance & 80–90 & 50–60 \\ \hline Incident handling & 90–95 & 80–90 \\ \hline \hline \end{tabular}  
* Costs, personnel, training, tools, etc.  
\end{table} 
Table 3: Results of resource consumption from applying 3D management in the case study compared with the existing 2D system (excluding resources associated with the GIS and BIM modeling process). with and analyze data more intuitively. By fostering this interoperability, the research aims to enhance management practices and improve operational outcomes in built environment applications. Successful BIM implementation relies on a comprehensive skill set that includes both technical proficiency and a deep understanding of the various disciplines involved in the construction process. Additionally, generating a GIS-3D city model presents several key challenges, including accurately extruding 3D volumes from building footprints and low-quality LiDAR point clouds, as well as creating realistic facade representations (LoD 3) using retouched on-site photographs. The LiDAR point cloud plays a critical role in the integrated GIS and BIM model by providing a template for defining the contours of the terrain, buildings, and other elements within the GIS environment. LiDAR captures high-resolution 3D data, offering precise coordinates that enable GIS software to delineate the geometric boundaries of various features. These contours form the foundation for generating 3D models, facilitating the development of accurate digital representations of the built environment. Integrating LiDAR data with BIM significantly enhances visualization and spatial analysis, thereby improving decision-making in urban planning, construction, and facility management. The primary advantage of integrated GIS and BIM models lies in their ability to encapsulate geometric or semantic information in a 3D format as a virtual library, accessible to stakeholders for evaluating and making decisions regarding process development. This capability helps reduce resource consumption, including time, costs, personnel, training, and tools. While integrating GIS-3D and BIM offers significant opportunities for enhancing building management and analysis, addressing the identified technical challenges is essential to fully realize the potential of these platforms. Continued research and development in this field is critical to achieving seamless interoperability between the two systems. Developing an integrated GIS and BIM simulation is challenging due to software incompatibilities, often requiring electronic links to incorporate external tools effectively.