## 4 BIM in the Facility Management of Infrastructure
### Tunnels  
Tunnels are the most monitored linear infrastructure. This is due to their features and safety requirements. From their design and construction phase to their operation and maintenance, they need a large amount of information. There are fewer BIM publications applied to this type of infrastructure compared to other constructions, especially in comparison with buildings. These studies are mainly focused on the incipient phases of the project, auscultation and construction control. For example, a BIM model was made during the construction of a mountain road tunnel in Israel to store the information for its use in its O&M [160], or in the road access tunnel for a hydroelectric power plant in Pakistan, where a BIM framework for construction management for drill-and-blast tunnelling has been implemented [161]. In both cases, they use commercial software such as Autodesk Civil 3D, Revit or Dynamo to visualise and manage the documentation during construction. In addition, they continue to use traditional project documentation (spreadsheets, text documents and two-dimensional CAD plans). The BIM model has also been used for the identification of risks during the construction of a metro tunnel in Wuhan (China) using IFC open standards [162]. More academic studies focus on facilitating decision making in the design phase. For example, a BIM model has been developed in Slovenia that is able to synchronise and transfer the structure geometry for the subsequent finite element analysis of the interaction of the structure with the ground [163]. In this sense, other publications explore the level of detail required from a parameterised model to reduce the cost and time of computation during the study of alternatives in the design phase for a tunnel [164; 165]. On the other hand, the application of open standards has been studied for the validation of the position and assembly of each ring of the structure in the Wuhan Yangtze River tunnel in China. This tunnel is 4650 m long and 15.2 m in section diameter that combines an urban motorway and an underground line [166]. Another study looks at the hardware and commercial software requirements needed to implement a collaborative platform, which was put into practice in two railway tunnels during construction in China [167]. In China too, an automatic monitoring system has been developed for a mountain tunnel construction. Monitoring is carried out at three levels. The first level collects information by sensors such as the groundwater level or the settlement of the tunnel vault. The collected information is transferred in real time over wireless networks. On a second level, this information is transmitted using satellite communication. Finally, the information is processed, analysed in the cloud, compared with the BIM model, and visualised in the digital twin. The system sends the information to the operators, and an automatic early warning is given in case of a failure [105]. Another example is the application of Construction-Operations Building information exchange (COBie) standards combined with Semantic Web technologies for the analysis of fan failure causes in Wenyi Road Tunnel in Hangzhou, China. This study demonstrates the decision analysis process for the O&M of the tunnel based on Digital Twins. However, the study finds some limitations such as the dynamic interaction between the visualisation model and the semantic reasoning model [24]. Nevertheless, most of the publications integrating these technologies come from urban service galleries. The sensor implementation is easier in this type of tunnel and, consequently, at CC and results visualisation in the BIM model for O&M [106; 108; 120; 168; 169; 106]. In the urban environment, BIM has been implemented for the O&M of the 24 km network and 23 underground stations in the Taiyuan metro (China). The case study aimed at the data retrieval, analysis, management, and transfer of the required information. The study involved staff from the O&M departments and established a level of detail appropriate to the needs.