China News Service, Nanjing, June 28th (Reporter Shen Ran Zhang Chuanming) On the morning of June 28th, as the Secretary of the Jiangsu Provincial Party Committee Lou Qinjian announced the start of Helong, the last set of coarse aggregate active powder concrete was slowly poured into the horizontal wet joint , The world's first light-weight steel-concrete structure cable-stayed bridge-Nanjing Fifth Yangtze River Bridge (hereinafter referred to as Nanjing Fifth Bridge) is connected in the rain and mist of the Yangtze River. The "smallest" brother in the Nanjing Yangtze River Bridge series will not only connect the two "newest" urban areas in Nanjing-Hexi New City and Jiangbei National New Area, but also connect a high-speed railway north of Nanjing to the south of Nanjing Station and fast track to Lukou International Airport.
The world's first light-weight steel-concrete structure cable-stayed bridge-Nanjing Fifth Yangtze River Bridge. (Information) Photo by Zhao Zhenyu
The Nanjing Five Bridge was built by the Nanjing Public Engineering Construction Center. It is located about 5 kilometers downstream of the Nanjing Third Bridge and about 13 kilometers upstream of the Nanjing Yangtze River Bridge. The total length is about 10.33 kilometers. The bridge is a central double-cable three-tower composite beam cable-stayed bridge The main bridge across the river is about 4.134 kilometers long. Both main spans of the main bridge are 600 meters and the total span is 1796 meters. It is designed as a two-way six-lane first-class highway with a speed of 100 kilometers per hour.
The main bridge part of the Nanjing Five Bridge consists of three steel-concrete composite towers standing in the Yangtze River. From a distance, it looks like three jade pillars dot the river surface, connecting the bridge deck of Bailian Hengjiang River. The radial white stay cable is from the top of the tower The extension to the bridge deck is extremely light compared to the few "Brother Bridges" not far away.
"From the pylon to the composite beam, this is the first large-span bridge with a real steel-concrete composite structure." Wu Huanling, director of the Nanjing Public Engineering Construction Center, told reporters that behind this "mix and match" combination is a series of technological innovations Among them, the key technology of the steel shell-concrete composite tower supported by the bridge construction team and Tsinghua University, Southwest Jiaotong University, etc. won the 2019 China Highway Society Science and Technology Special Award.
Wet joint pouring of the Helong section of Nanjing Five Bridges. (Information) Photo by Zhao Zhenyu
According to Wang Hui, deputy manager of the Nanjing Fifth Bridge Project of CCCC Second Aviation Administration, the construction side is very different from the traditional bridge-building technology. It is the proportion of the factory and assembly construction of the main bridge of the fifth Yangtze River Bridge in Nanjing that is as high as 80%. “For the first time, the main tower of the bridge innovatively uses a steel shell concrete structure. Not only is the steel shell produced in the factory, but most of the steel bars are also pre-pierced in the factory and hoisted and assembled with the steel shell. The construction site only needs to weld the steel shell ring joints and connect the segments Reinforcement and pouring concrete. The modular building scheme of building blocks reduces the intensity and difficulty of field operations, improves the speed and quality of the project, and greatly reduces the impact on the bridge environment and the ecology of the Yangtze River."
On the morning of the 28th, the Helong scene in heavy rain. Photo by Zhao Zhenyu
“The main beam of Nanjing Five Bridge also used the new material—coarse aggregate active powder concrete for the first time, which has the advantages of high strength, low cost and light weight. The material is applied to the steel-concrete composite beam bridge deck, which not only reduces the bridge The weight of the bridge makes the bridge look lighter, and at the same time effectively avoids the fatigue cracking and pavement problems of the steel bridge deck, and also reduces the cost of asphalt pavement." Introduction.
The fifth Nanjing Yangtze River Bridge under construction. Live screen
Yang Tao, president of Nanjing Urban and Transportation Planning and Design Research Institute, believes that Nanjing has transformed from a riverside city dominated by the main city of Jiangnan to a double city of Jiangnan and Jiangbei. The urgent needs of residents. "As the fifth cross-river bridge in the Nanjing section of the Yangtze River, it is also one of the 27 river crossings planned by Nanjing. The task of the Nanjing Five Bridge is to communicate with the Nanjing Second Yangtze River Bridge across the river and form a loop to ease the surrounding area. Transit traffic, while taking into account the transportation links between Nanjing's new districts and new districts, also opened up a fast lane for Jiangbei National New District to connect the high-speed railway Nanjing South Station and Lukou International Airport. important meaning."
With the completion of Helong, it is expected that the bridge will be officially opened to traffic by the end of this year without a toll station, and it will become another free bridge to cross the river after the Nanjing Yangtze River Bridge. (Finish)