Morning of june 28
With the last plate of coarse aggregate active powder concrete
Slowly poured into the horizontal wet joint
Nanjing Yangtze River Fifth Bridge crosses the main bridge smoothly
Nanjing Fifth Yangtze River Bridge. Photo by Zhao Zhenyu
So far, following the second, third and fourth bridges
Nanjing Yangtze River Bridge in 1968
New brother
Nanjing Yangtze River Bridge: Five brothers, hello
Another giant dragon flying north and south of the Yangtze River
On one side is the "nearest future" of the national Jiangbei New District, on the other side is the "newest city" of Nanjing Hexi New City.
The fifth Yangtze River Bridge in Nanjing has not been "born", it has already attracted much attention.
The "every move" of the Fifth Bridge affects the hearts of the citizens. As early as May, learning that the main bridge was expected to end at the end of June, photography enthusiasts rushed to the construction site of the fifth bridge, "small planes" and long guns and short guns "coming into battle" to shoot precious pictures.
"The streets and alleys are talking about Helong news, and the friends in the circle of friends are all kinds of good things..." The Five Bridges, which will be opened to traffic at the end of the year, make people look forward to the development prospects of Nanjing.
An expert who participated in the construction of the bridge lamented that this kind of "participation of the whole people" scene is indeed rare since the Nanjing Second Bridge was opened to traffic.
Picture of the Nanjing Yangtze River Fifth Bridge construction process. Photo by Zhao Zhenyu
Why is it so popular? Some people have given the answer: The main bridge of Nanjing Yangtze River Five Bridge is the world's first composite beam cable-stayed bridge with coarse aggregate active powder bridge deck structure, and the world's largest steel-concrete composite cable tower. Pull bridge.
The Nanjing Yangtze River Fifth Bridge is located about 5 kilometers downstream of the Nanjing Third Yangtze River Bridge and about 13 kilometers upstream of the Nanjing Yangtze River Bridge, with a total length of about 10.33 kilometers.
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 of the bridge has three steel-concrete composite pylons standing in the middle of the Yangtze River. When viewed longitudinally, it looks like three white hostas adorning the river. The main beam of the bridge is divided into 123 beam sections, and the standard beam section adopts narrow-body intelligent hydraulic lifting bridge deck crane symmetrically suspended.
The Helong beam section is 35.6 meters wide, 14.125 meters long, and has a lifting weight of 405.1 tons. They have to "hand in hand" with the last section of the South Tower and North Tower, respectively, to realize the two main spans of Helong.
On June 28, the Helong ceremony site.
The construction of this bridge is also deeply concerned by the domestic and international bridge community.
"From the tower to the composite beam, this is the world's first truly large-span steel-concrete composite bridge." Wu Huanling, director of the Nanjing Public Engineering Construction Center, introduced that the tower of the Nanjing Second Yangtze River Bridge is a concrete structure, and the Yangtze River III The bridge tower is made of all-steel structure. The fifth Yangtze River Bridge in Nanjing combines the strengths of both. It not only has the durability of the steel tower, but also has a moderate cost.
Behind this "mix and match" combination is a series of technological innovations. The construction team teamed up with Tsinghua University and Southwest Jiaotong University to solve the key problem. The key technology of steel shell-concrete composite pylon has won the 2019 China Highway Society Science and Technology Special Award.
"The new material used for the main beam of Nanjing Five Bridge-coarse aggregate active powder concrete, has the advantages of high strength, low cost, and light weight. This material is applied to the steel-concrete composite beam bridge deck, which reduces the weight of the bridge. It makes the bridge shape lighter, 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."
Ai Xiu, the person in charge of the Nanjing Five Bridge Project of China Communications Second Aviation Administration, introduced that the fifth Yangtze River Bridge in Nanjing is also the world’s first composite beam cable-stayed bridge using coarse aggregate active powder concrete bridge decks, constantly refreshing the world in structural technology. Record.
On June 7, the fifth Nanjing Yangtze River Bridge under aerial photography was constructed. Photo by Tuobo
On June 7th, the middle tower and the two bridge deck cranes were like a huge "balance". Two giant steel-concrete composite beams were smoothly hoisted to Helongkou, officially opening the prelude of the main bridge Helong.
In the next week, the bridge construction team completed the connection between the 20th beam section and the 19th beam section of the central tower, and then installed and tensioned through the stay cable. The height and gap between the Helong beam sections were getting closer and closer. The bridge The bridge deck increasingly approached a complete arc, and Helong was close at hand.
On June 7, the fifth Nanjing Yangtze River Bridge under aerial photography was constructed. Photo by Tuobo
"Don't look at this gap is very small. In Helong, the height matching between the two beam sections and the overall line shape are very important, there must not be a slight deviation." Wang Hui, deputy manager of the Nanjing Five Bridge Project of China Communications Second Aviation Administration.
After the composite beams are in place, the thrust system installed in the north tower and the south tower in advance performs simultaneous thrusting. With the precise control of the tension of the stay cables, the gap between the two main spans and the closing beams continues to decrease.
Late at night on June 15th, there was a lot of cheers at the construction site of the Nanjing Yangtze River Fifth Bridge, and the most critical step in the construction of Helong—the push of Helong was successful.
"The final push was completed very quickly. Most of the time was spent on matching measurement and debugging. I can’t remember how many times the measurement and adjustment were made. There must be dozens of times. It must be accurate to 1 mm. Because The webs and roof of the composite beam are connected by high bolts. If it exceeds 1 mm, let alone the nails, the high bolts cannot pass through, and it is not even a millimeter away. There are 4 Helongkous in the middle and side spans of the Nanjing Five Bridge. A piece of craft splicing board is useless. It perfectly realizes the bolting dragon and creates a miracle in the history of bridge construction." Wang Hui said.
Picture of the Nanjing Yangtze River Fifth Bridge construction process. Photo by Zhao Zhenyu
Unlike many bridge veterans, the main bridge of Nanjing Fifth Yangtze River Bridge is 80% industrialized and assembled. Not only is the upper composite beam produced by the factory, but the main tower is also the first to adopt a steel shell concrete structure, of which the steel shell Produced in the factory, most of the steel bars are pre-pierced in the factory and are hoisted and assembled with the steel shell as a whole. The construction site only needs to weld the steel shell girth, connect the inter-segment reinforcement and cast concrete.
"After the opening of the Nanjing Five Bridge, it is conservatively estimated that the daily traffic volume is about 40,000. Both the rapid loop function and the transit vehicles are expected, and the traffic volume is expected to increase rapidly," said Zhang Dengjing, deputy director of the Nanjing Public Construction Center.
After the bridge is closed, the entire project construction will enter the pavement construction stage, including the installation of ancillary facilities such as asphalt paving, street lamps, anti-collision guardrails, sound barriers, etc., to sprint to achieve the goal of opening to traffic.
Nanjing Yangtze River Fifth Bridge is an important link connecting the main urban area with the Jiangbei New District. After the completion of the bridge, the regional backbone road network will be improved, the development of the Yangtze River Economic Belt will be further promoted, and the layout of national trunk roads and river crossing channels in the lower reaches of the Yangtze River will be improved.
At the same time, it is of great significance for alleviating the traffic pressure across the river, accelerating the construction of the Jiangbei New District in Nanjing, accelerating the strategy of “development along the river and crossing the river”, enhancing the comprehensive strength of the city in Nanjing and expanding the urban space.
Inventory of the bridge over the Nanjing section of the Yangtze River
"The mountains are not far away, the water is not close."
The Yangtze River is not only a "golden belt" between the horizontal cities along the river, but also a "barrier belt" between the north and the south.
In order to cross the sky and promote the integration and development of the two sides of the Yangtze River, Jiangsu has been accelerating the planning and construction of the river crossing.
According to the plan, by 2035, there will be 45 river crossings under construction and under construction in Jiangsu, with an average of one every 10 kilometers. Both sides of the Yangtze River will be multi-channel, barrier-free, convenient and efficient.
The picture shows the Nanjing Yangtze River Bridge, which was opened to traffic in 1968. Photo by Tuobo
Do you remember what the elementary school textbook said?
"In the early morning, I came to the Nanjing Yangtze River Bridge. Today's weather is exceptionally good, and there are many white clouds floating in the sky. The bridge looks very magnificent under the bright sunshine..."
"The surging rivers are vast and rushing towards the sea. The Yangtze River, which has been called Tiancao since ancient times, was conquered by us. A bridge flew north and south, and the Tiancao became accessible."
The Nanjing Yangtze River Bridge is described here.
From the Qianli Wuyi Bridge before the liberation, to the double-decker railway and highway dual-use bridges designed and built by China after the founding of New China.
In 1968, the Nanjing Yangtze River Bridge was completed and opened to traffic.
As the "big brother" who has been known as the "contending bridge" since childhood, the Nanjing Yangtze River Bridge was an important milestone for China's economic construction in the 1960s.
The picture shows the Nanjing Second Yangtze River Bridge is a cable-stayed bridge across the Yangtze River. Photo by Tuobo
Nowadays, dozens of river crossings cross the horizon, and the record of super bridges in New China has been refreshed on the Yangtze River.
On the surface of the Nanjing section of the Yangtze River, the Yangtze River Bridge, the Second Yangtze River Bridge, and the Third Yangtze River Bridge... Modern bridges with different shapes span across each other, becoming a "conveyor belt" for the booming economic development of the north and south of the Yangtze River.
The aerial photography of Nanjing's Third Yangtze River Bridge is fascinating against the sunset. Photo by Tuobo
The Fourth Nanjing Bridge that spans the Yangtze River is known as "China's Golden Gate Bridge". Photo by Tuobo
The aerial photography connects the fourth bridge of Nanjing between the north and south of the Yangtze River. Photo by Tuobo
The picture shows the "Nanjing Eye", the first sightseeing pedestrian bridge on the Yangtze River, located at the central axis of the Youth Olympics axis in Hexi New City, Jianye District, Nanjing City, crossing the Nanjing Yangtze River and Jiajiang River. Photo by Tuobo
Nanjing Dashengguan Yangtze River Bridge is a high-speed railway bridge project across the Yangtze River. Photo by Tuobo
Author: Xu Shanshan Zhao Zhenyu Yang wave chuanming