【Explanation】On June 28, the fifth bridge of Nanjing Yangtze River, located about 13 kilometers upstream of the Nanjing Yangtze River Bridge, smoothly closed.
[Explanation] The project started from the Wuli Bridge Interchange in Jiangbei New District of Nanjing. After crossing the main channel of the Yangtze River, the first bridge crossed the Jiangjiang River, arrived at Jiangshan Street, Jianye District, Nanjing, and connected to the underground project of the Youth Olympic axis. The total length of the route is 10.33 kilometers, the bridge across the main river is 1796 meters long, and the Jiajiang tunnel is about 1755 meters long. The shield tunneling method is used to cross the Jiajiang section.
[Same period] Lai Yongman, the person in charge of the site of Nanjing Yangtze River Fifth Bridge, Nanjing Public Engineering Construction Center
The fifth bridge is an important part of our city loop and an important transportation link. After completion, it will only take 10 minutes from (Jianye District) Hexi Olympics to Jiangbei New District.
[Explanation] Lai Yongman told reporters that the fifth innovation of the Nanjing Yangtze River Fifth Bridge is the most innovative. It is a bridge built like a building block. The main tower, deck, pier and other components of the bridge are completed at the factory and then transported to the construction site for assembly.
[Same period] Lai Yongman, the person in charge of the site of Nanjing Yangtze River Fifth Bridge, Nanjing Public Engineering Construction Center
In terms of technological innovation, for the first time, a lightweight steel-concrete composite structure of composite towers and beams is used. The composite towers give full play to the joint performance of steel and concrete. This structure has high bearing capacity, strong durability, convenient construction and appearance. Pretty. The normal pylon is about 8 meters 6 in width. Our pylon is only 5 meters 8 in width, so it looks slim (slender).
[Explanation] In the construction, the bridge and tunnel project uses ultra-high-performance concrete, adding "coarse aggregate" and "fine aggregate" when pouring, which makes the strength of the concrete poured several times, effectively saving materials and construction costs .
[Same period] Lai Yongman, the person in charge of the site of Nanjing Yangtze River Fifth Bridge, Nanjing Public Engineering Construction Center
This material contains "coarse aggregate" and "fine aggregate", including steel fiber and other materials combined together. It has high strength, high modulus and low shrinkage. Its strength can reach more than 150 MPa. Three times the strength of traditional concrete, the thickness of the bridge deck is only 17 cm, and the weight of the bridge is reduced. Reduced material costs, including our construction costs, and accumulated cost savings of approximately 45 million yuan.
[Explanation] It is understood that the Nanjing Yangtze River Five Bridges Jiajiang Tunnel has a shield section length of 1159 meters and a segment outer diameter of 15 meters. It is currently the largest diameter underwater shield highway tunnel under construction in China. The results are remarkable.
[Same period] Wu Wenqing, Chief Engineer, Project Department, China Railway 14th Bureau Group
The Wuqiao Jiajiang Tunnel uses a high-precision three-dimensional laser tracking scanner to control the prefabrication precision of the segment, and develops an automatic monitoring and early warning system for the segment floating, which ensures the quality of the forming tunnel. At the same time, through the research on the environmental protection and reuse of shield waste slurry, all the waste residue formed by separation and pressure filtration was used for the transformation of Meizizhou Youth Olympic Park and Jiajiang Embankment. All the waste residue generated in the entire tunnel was turned into waste "Treasure", realized the reuse.
[Explanation] After the completion of the Helong, the builder will also carry out a complete set of bridge deck system construction operations including paving, anti-collision railings, lighting facilities, strong and weak electricity, and drainage systems. At the same time, the necessary structural durability will also be carried out For sexual protection operations, load experiments must be verified before opening to traffic. It is expected that by the end of this year, the fifth Yangtze River Bridge in Nanjing will be ready for traffic.
Reporter Ge Yong from Nanjing, Jiangsu
Editor in charge: [Li Yuxin]