# Digital Twins' Application for Geotechnical Engineering:
## 2 The Current Situation of Digital Twins in Geotechnical Engineering
By developing dynamic digital twin models, the system achieves predictive energy demand fluctuation analysis and optimized distributed energy allocation, providing decision-support tools for smart city infrastructure planning. [PERSON] et al. [26] applied digital twin technology to underground space visualization, underground construction, and underground disaster prevention monitoring and analysis, and they established an intelligent overall planning model for underground space based on a digital twin model. The Xiongan New Area, which is currently under construction, uses digital twin technology to simulate urban construction and traffic flows, helping planners design more efficient and sustainable transportation systems to enhance citizens' travel experience. The application of digital twin technology in urban construction not only helps to improve efficiency and optimize resources but also enhances the resilience and sustainability of cities. By creating a virtual city model, it can monitor, predict, and respond to various challenges in urban development in real time, and can promote the development of cities in the direction of intelligence, greenness, and sustainability. In the field of transportation:  
In the field of traffic and tunnel engineering, digital twin systems can achieve intelligent and optimized traffic management, from traffic flow monitoring and intelligent signal control to accident prevention and infrastructure management. Through real-time data collection and analysis, digital twins provide decision-makers with more accurate decision support, greatly improving the safety, efficiency, and sustainability of road traffic. This is conducive to the overall goal of \"measurable, knowable, controllable and serviceable\" in transportation and tunnel engineering. For example, the Helsinki Metro Line Extension Project in Finland has improved the efficiency of all stages of project planning, design, construction, and operation through the use of digital twin technology. The Zayed Port Infrastructure Project in Abu Dhabi has improved the design accuracy, construction efficiency, and operation management level of the project through digital twin technology. Daxing International Airport in Beijing has also widely adopted digital twin technology  
Figure 2: Digital twin system for urban flooding disaster assessment and pre-warning (reproduced from [PERSON], [PERSON] et al. [24]). in all stages, from design and construction to operation, which not only improves the construction efficiency and quality of the project but also provides intelligent solutions for the long-term operation and maintenance of the airport. [PERSON] [27] used the AI digital twin monitoring linkage system to achieve all-weather and all-elements monitoring of expressway tunnels, completing real-time monitoring of traffic parameter data and traffic events in the tunnel, and synchronizing warnings with LED screens, smart cloud broadcasting, induction devices, lane control lights, etc., to achieve the safe operation supervision level and efficiency of vehicles in expressway tunnel sections. [PERSON] et al. [28] established a set of expressway tunnel early warning platforms based on digital twin technology, AI, AR, VR, MR, and other technologies, which can be applied to different scenarios of expressway tunnels to achieve all-weather monitoring of expressway tunnels and solve the problem of safety hazards in expressway tunnels. [PERSON] et al. [29] proposed a digital twin architecture of highway traffic. Through this architecture, a digital twin platform for highway traffic supporting \"state perception-digital experience-aided decision-optimization control\" was established and applied to road engineering projects in Nanjing, Wuxi, Dalian, and other cities. Figure 3 shows the Digital Twin System Architecture of Highway Traffic.