On the 19th, the 2024 "Suzhou-style Maintenance" Technical Exchange Conference, themed "Smartly Painting a New Scene of Jiangsu Roads, Continuing the Glorious Journey of Connectivity," was held in Jiangyin, Jiangsu. The Jiangyin Bridge—the cross-river "throat" of the Beijing–Shanghai Expressway and China's first super-large steel box girder suspension bridge with a main span exceeding one kilometer—became the main subject of research, discussion, and learning at the conference, showcasing to experts and representatives from expressway operation and maintenance units and transportation research institutions across the country various achievements in integrated construction, management, and maintenance of cross-river channels, innovation in super-long-span bridge maintenance, and the construction and development of digital bridges.

This "Suzhou-style Maintenance" Technical Exchange Conference was hosted by Jiangsu Communications Holding Co., Ltd. and the Highway Branch of the Jiangsu Provincial Society for Comprehensive Transportation, and organized by Jiangsu Yangtze River Expressway Channel Management Co., Ltd. and Jiangsu Expressway Engineering Maintenance Technology Co., Ltd. Since its inception in 2017, the "Suzhou-style Maintenance" Technical Exchange Conference (Forum) has gradually become a shared exchange platform based in Jiangsu, oriented toward the whole country, and possessing regional influence—a distinctive calling card of Jiangsu expressway maintenance that integrates technical exchange, industry-academia-research-application, and collaborative cooperation.

Taking the 25th anniversary of the opening of the Jiangyin Bridge and the Guangjing–Xicheng Expressway as an opportunity, this conference reviewed the development history of the Jiangyin Bridge in the stages of design, construction, and maintenance operation, and conducted special report exchanges on key technologies for cross-river bridges such as "digital bridge construction," "structural health monitoring," and "cable system maintenance," providing valuable experience for the construction and operation management of river-crossing channels.

The Jiangyin Bridge is a key basic construction project of the national "Ninth Five-Year Plan" approved by the State Council. It was completed and opened to traffic on September 28, 1999, representing the highest level of bridge-building in the 1990s and leading the widespread application of "kilometer-span" technology. In the 25 years since opening, the Jiangyin Bridge has withstood the tests of heavy traffic volume, many heavy-load vehicles, and long service time. Behind its healthy operation is the support of advanced technology and high-level maintenance:

In 2004, the bridge conducted full-bridge tests on the main deck pavement layer, extending the service life of the pavement; in 2006, the main cable protection system was upgraded, effectively preventing further corrosion of the main cable steel wires; in 2007, preventive maintenance coating was applied to the main towers, marking the first time in China that a dehumidification system was added to an existing suspension bridge; in 2011, a complete set of treatment technologies for fatigue cracks in steel box girders was developed and applied, and a steel box girder maintenance management system was developed, creating a digital archive for each crack and providing a basis for subsequent repair of fatigue cracks.

At the same time, the Jiangyin Bridge has also undertaken many experiments in cross-river channel maintenance: in 2014, in order to fully understand the health condition of the Jiangyin Bridge under high traffic volume and a high proportion of heavy loads, the bridge carried out China's first comprehensive and in-depth full-bridge structural condition inspection. The results showed that key measurement points such as strain, main cables, and main girders all met design requirements, and the overall stress condition of the main bridge structure was good; in 2018, in order to understand the law of preload loss in cable clamp bolts, the bridge carried out China's first bolt replacement construction on a suspension bridge during operation, forming a complete set of bolt replacement construction techniques. A new type of self-lubricating bushing was developed, improving the service life of the suspenders and solving the difficult problem of detecting corrosion in concealed parts of the suspenders; in 2019, the Jiangyin Bridge and the Guangjing–Xicheng Expressway carried out a centralized maintenance project, pioneering centralized maintenance of high-traffic expressways in China. This demonstration project won the Special Prize in the Highway Industry Maintenance Engineering Innovation Case awards; in 2023, the Jiangyin Bridge took the lead in China in exploring "unmanned" maintenance inspections of cross-river bridges, using drone airports to achieve a series of new digital application practices such as "nanny-style" regular inspections, defect registration, and cloud-based records.

Years of exploration and practice have yielded fruitful results in the maintenance of the Jiangyin Bridge: more than 20 years of maintenance and management experience have been summarized into volumes. Not only was the "Maintenance Manual" revised, but a blue book in the maintenance field was also published, resulting in a total of 6 monographs on bridge maintenance and 3 maintenance methods; during this period, the technical specifications for the maintenance of highway cable-structure-system bridges, co-compiled by the maintenance team, also became the first national-level technical specification in China and abroad for the maintenance of highway cable-structure-system bridges, filling a gap in the industry.

Through continuous maintenance practice, the Jiangyin Bridge is accelerating digitalization and promoting the intelligent upgrading of maintenance work. Relying on China's first regional long-span bridge health monitoring data center established in Jiangsu Province, the Jiangyin Bridge now has full-life-cycle maintenance management technical support. By integrating digital achievements such as the health monitoring system, service perception system, main cable dehumidification system, and bridge anti-collision warning system, and continuously improving digital models and specialized algorithm research, the Jiangyin Bridge has built a comprehensive digital bridge platform covering data services, equipment control, smart operations, scientific management and maintenance, and convenient services. Experts at the conference believe that the deep digitalization of the Jiangyin Bridge not only provides intelligent maintenance support for itself, but can also export management and maintenance experience to similar long-span bridges across the country.