The worlds longest bridge, the Jiaozhou Bay Bridge in north-eastern Shandong Province, China made the Forbes list of the worlds 11 most incredible bridges in 2011.
Construction of the Jiaozhou Bay Bridge (also known as Qingdao Haiwan Bridge) officially started on June 30th 2007. At 26.4 miles long the bridge is the longest sea spanning bridge in the world, connecting Qingdao and Huangdao. Chinese officials said the bridge was designed to be strong enough to withstand a magnitude 8 earthquake, typhoons, or the impact of a 300,000 ton vessel and according to the judges, 'Construction of the bridge is a technological miracle', hailing China's advanced level of architecture and technological development.
The bridge was completed on June 28th 2011. The design lifetime is 100 years, which requires not only durable concrete technology but also high performance protective coatings. After a long period of survey and investigation, pure polyurea became the best choice for this protective aim. The bridge was actually coated with polyurea coating during construction. The polyurea was provided by Qingdao Shamu International Trade Co. Ltd.
The application was completed successfully under the supervision of Dr Weibo Huan, a professor at Qingdao Technological University, who is a pathfinder of polyurea technology and the chief scientist on the Beijing - Shanghai High Speed Railway polyurea protective project.
The Jiaozhou Bay Bridge is located in North China, where there are 50-60 days of frozen-thawed time per year. The bridge required:
- A versatile coating with fast cure against high humidity.
- High thick film building, high tensile strength.
- High elongation at break.
- High impact resistance.
- High abrasion resistance.
- UV stable with 100 years durability.
All of the above criteria were achieved with the use of polyurea