# Digital Twin Framework for Road Infrastructure Management
## 4 Digital Twin Framework for Road Infrastructure Management
### Analysis of Existing DT Frameworks for Road Infrastructure Management
#### 4.1.4 Other Applications in Civil Infrastructure and Urban DTs
This approach aims to extend the framework to encompass network- and city-level management rather than concentrating solely on single asset management. The number of DT layers typically ranged from three to five, which indicates a small fluctuation. Similar to the other three road domain DTs, inconsistencies in the naming and roles of layers must be addressed when deriving a comprehensive and integrated DT framework. Additionally, as in the previous three cases, the components and functionalities of each layer should be considered in establishing a comprehensive DT framework for road infrastructure management. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Author** & **Application** & **Application/Purpose** & & **DT Layers** & **Layer Type** \\ \hline \multirow{4}{*}{[PERSON] et al. [48]} & \multirow{4}{*}{Dynamic city DT (buildings)} & \multirow{4}{*}{Decision-making for O\&M at the building and city levels} & \(\bullet\) & Data acquisition layer & \multirow{4}{*}{Applied/ Validated} \\  & & & & \(\bullet\) & Transmission layer & \\ \cline{3-5}  & & & \(\bullet\) & Digital modeling layer & & \\ \cline{3-5}  & & & \(\bullet\) & Data/ model integration layer & & \\ \cline{3-5}  & & & \(\bullet\) & Service layer & & \\ \hline \multirow{4}{*}{[PERSON] et al. [27]} & \multirow{4}{*}{Smart city (automotive)} & \multirow{4}{*}{Car-as-a-Service/ Smart cities} & \(\bullet\) & Observable asset model & \multirow{4}{*}{} \\  & & & \(\bullet\) & Storage & \\ \cline{3-5}  & & & \(\bullet\) & Communication interface & & \\ \cline{3-5}  & & & \(\bullet\) & Digital twin & & \\ \cline{3-5}  & & & \(\bullet\) & Tools and utilities & & \\ \cline{3-5}  & & & \(\bullet\) & HMI & & \\ \hline \multirow{4}{*}{[PERSON] et al. [49]} & \multirow{4}{*}{Urban DT} & \multirow{4}{*}{Conceptualization of DTs in urban management} & \multirow{4}{*}{Digital modeling layer} & \multirow{4}{*}{Generic/ Conceptual} \\  & & & \(\bullet\) & Simulation layer & & \\ \cline{3-5}  & & & \(\bullet\) & Service/ actuation layer & & \\ \hline \multirow{4}{*}{[PERSON] et al. [28]} & Smart asset management (building/ infrastructure) & \multirow{4}{*}{DT-enabled asset management} & \(\bullet\) & Smart asset layer & \multirow{4}{*}{Generic/ Smart DT-enabled asset management layer} & \multirow{4}{*}{Conceptual} \\  & & & \(\bullet\) & Smart asset integration layer & & \\ \cline{3-5}  & & & \(\bullet\) & Smart DT-enabled asset management layer & & \\ \hline \multirow{4}{*}{[PERSON] et al. [50]} & \multirow{4}{*}{DT for urban underground space} & \multirow{4}{*}{Maturity levels of DTs for underground spaces} & \(\bullet\) & Physical layer & \multirow{4}{*}{Generic/ Conceptual} \\  & & & \(\bullet\) & Data acquisition layer & \\ \cline{3-5}  & & & \(\bullet\) & Communication/transmission & & \\ \cline{3-5}  & & & \(\bullet\) & Data management layer & & \\ \hline \multirow{4}{*}{[PERSON] et al. [51]} & Civil and infrastructure (emergency management) & DT system architecture for emergency management of civil infrastructure & \(\bullet\) & Physical layer & \multirow{4}{*}{Generic/ Conceptual} \\  & & & \(\bullet\) & Data layer & \\ \cline{3-5}  & & & \(\bullet\) & Digital modeling layer & & \\ \cline{3-5}  & & & \(\bullet\) & Data/ model integration layer & & \\ \cline{3-5}  & & & \(\bullet\) & User interaction layer & & \\ \hline \multirow{4}{*}{[PERSON] et al. [52]} & \multirow{4}{*}{Future construction management} & Strategic roadmap for synchronized construction management in Construction 4.0 & Infrastructure layer & \multirow{4}{*}{Generic/ Electrical} \\  & & & \(\bullet\) & Sensor and tag layer & & \\ \cline{3-5}  & & & \(\bullet\) & Digital layer & & \\ \cline{3-5}  & & & \(\bullet\) & Service layer & & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: DT-layer-based implementations for other civil infrastructures and urban DTs.