In order to realize the knowability and measurability of the lifeline state of the bridge at each stage, it is particularly important to timely understand and master the health dynamics and safety status of the bridge, verify the design theory and guide the subsequent design of the same type of bridge, which is particularly important to establish a scientific health and safety monitoring system during the operation period.

In recent years, transportation, as one of the main contributors to economic development, has developed rapidly. And bridges play a huge role as connecting transportation lines.

As an important carrier of public transportation, bridges play a vital role in the smooth operation of regional transportation and social and economic development. With the rapid development of social economy, the traffic flow of bridges has increased rapidly, and the impact of bridge safety hazards has intensified. Bridges are damaged due to factors such as harsh use environment, load action, and long age, resulting in diseases, threatening bridge safety and causing bridge accidents.

In recent years, bridge safety accidents have occurred frequently, with huge social impact and serious consequences of endangering people's lives. The Ministry of Transport's "Opinions on Further Improving the Safety and Durability of Highway Bridges" Jiao Highway Fa [2020] No. 127 stipulates: "By the end of 2025, the health monitoring system of special bridge structures such as cross-river, cross-sea and cross-canyon will be fully covered." By 2035, the level of highway and bridge construction and maintenance management will enter the forefront of the world. ”

In order to realize the knowability and measurability of the lifeline state of the bridge at each stage, it is particularly important to timely understand and master the health dynamics and safety status of the bridge, verify the design theory and guide the subsequent design of the same type of bridge, which is particularly important to establish a scientific health and safety monitoring system during the operation period.

In the past, the bridge safety inspection method was mainly for technicians to regularly inspect the bridge and road site, and the work efficiency was low, and the current highway bridge management system data collection was basically based on manual collection, which required the naked eye to observe all parts of the bridge, and then manually recorded and entered, and the accuracy was poor. And because of the large number of bridges, inspection methods cannot effectively evaluate all bridges, often missing important information about dangerous bridges, resulting in risks that could have been avoided.

With the continuous development of the Internet of Things, big data, and smart cities, the health and safety monitoring of bridges and the maintenance of important structural parts are inseparable from the application of sensors. The development and application of some reliable, accurate and cheap new sensors (such as pressure sensors, displacement measurement sensors, strain measurement sensors, vibration measurement sensors, etc.) have strongly promoted the development of intelligent bridge health and safety monitoring.

In July this year, the "Design Standard for Urban Bridge Digital Twin Monitoring System" jointly declared by Wuxi Municipal Government, Garden Bureau and Southeast University was approved by the Jiangsu Provincial Department of Housing and Urban-Rural Development, marking the official landing of the provincial standard compiled simultaneously with the project, and the digital twin monitoring of Jinkui Bridge is the first pilot in the province.

About 120 sensors of different categories will be installed on the Jinkui Bridge to achieve all-round real-time monitoring. The installed sensors include temperature and humidity sensors, inclination sensors, crack meters, static levels, ultrasonic flow meters, etc., which can be used to obtain full-dimensional data such as displacement, vibration, stress, and load during bridge operation.

It is reported that as the "capital of the Internet of Things", Wuxi has an earlier development of bridge health monitoring system, and bridges such as Ronghu Bridge, Kaiyuan Bridge and Lihu Bridge have been installed with sensors, which can update the basic information, disease status and maintenance records of each bridge in real time.

With the development of the economy, China's bridge construction has ushered in an unprecedented peak of development, providing a strong transportation guarantee for economic construction. According to statistics, the total number of bridges in the country exceeded 1 million in 2017, including high-speed rail bridges, urban large overpasses, etc.

The modern bridge safety monitoring system uses a variety of modern advanced technology means to realize real-time monitoring of bridge conditions through sensing technology and communication technology. Then conduct in-depth analysis of the monitoring data of various types of bridges, and issue timely early warnings when the safety status of the bridge is abnormal, so as to prevent safety accidents in the bridge and ensure the normal operation of the bridge.

With the rapid development of China's infrastructure construction, the health monitoring of bridges, railways and other projects has attracted increasing attention. By installing various sensors on the bridge to collect data such as stress, displacement, and acceleration, the instability of manual operation can be eliminated. Industry insiders believe that this is at least an industry of hundreds of billions of yuan per year, and if the model is extended to tracks, culverts and other fields, it will be a trillion-yuan industry.