Project description: At present, the testing level of old bridges in my country is developing slowly. The main test is to manually approach the site. The testing cycle is long, the cost is high, and the impact on traffic is great. Due to the above reasons, it is difficult to accurately determine the disease status of bridges, accurately measure key stress indicators in concrete structures, and learn the stress status and corrosion degree of steel bars and steel strands in the structure. These technical difficulties have led us to rely too much on experience and experts when dealing with these critically ill bridges. How to scientifically, accurately and promptly grasp the status of bridges is an urgent task. The intelligent bridge detection technology of Zhou Yongjun's team of Chang 'an University successfully solved the problems of difficulty in detecting bridges, roads and buildings in structural strain, deformation, prestress and appearance defects, and realized long-distance and portable dynamic detection of bridges, roads and buildings, which strongly supported the construction and development of major projects in my country. With the successful application of bridge deflection detectors, long-distance crack detection systems, multi-purpose strain measurement sensors, prestressed cable tension gauges, road detection drones and other equipment developed by the team in the Hong Kong-Zhuhai-Macao Bridge and the Shanghai-Tong Yangtze River Bridge, It has not only created a precedent for specifications and standard testing in the bridge testing industry, but also increased the number of HJ series of multi-purpose strain measurement sensors, The possibility of transferring technical achievements of long-distance deflection testing systems and other relatively mature bridge testing products. Prospects: Testing and monitoring are two different markets, and the cost of monitoring the market is about 5-10 times that of the testing market. About 5% of bridges need monitoring services every year, and there is a market of about 2 billion yuan. Calculated by province, the cost of testing and monitoring highways and national and provincial bridges in each province, autonomous region, and municipality directly under the Central Government is approximately 200 - 300 million yuan/year. The testing market in civil engineering industries such as municipal bridges, industrial and civil construction, water conservancy and hydropower industries is larger than the bridge market. It can also be explained from the business of testing institutions that there are only 100 Class A highway testing and testing institutions in the country (more than 1200 Class B institutions), with an annual output value of 100 - 200 million yuan (60%-80% of which are bridges), and road testing amounts to 10 - 20 billion yuan.