On the morning of December 22, by the Taizhou River, the temperature dropped to about minus 6 degrees Celsius. Despite the biting river breeze, on the Tianxingzhou special channel bridge of Changtai Yangtze River Bridge, people's mood is like the warm sunshine of the day. The bridge builders from the headquarters, construction units and design units witnessed the smooth closure of the world's largest span steel truss arch bridge for road and railway.
Among the excited crowds, Xia Pengfei, the executive deputy commander of the Changtai Yangtze River Bridge Construction Headquarters of the Jiangsu Provincial Transportation Engineering Construction Bureau, could not calm down for a long time: for 23 months, the Tianxingzhou special channel bridge with a main span of 388 meters finally achieved a high-precision closure with an error of no more than 2 mm, and the hard work of all the builders was finally rewarded. Next, another steel truss arch bridge on the Changzhou side, the Lu'anzhou Special Waterway Bridge, will also be closed within the year, so the established tasks of the bridge construction in 2023 will be completed.
The Changtai Yangtze River Bridge consists of a world's largest span cable-stayed bridge spanning the main channel and a world's largest span steel truss arch bridge on each side. These three world-class bridges are all asymmetrical structures, and in the future, the upper deck will be a highway, the lower deck will be a running car on one side, and the ordinary road on the other side.
"The steel truss arch bridge is not like the main channel bridge, the whole piece of the beam is lifted up and closed, it is carried out step by step. Xia Pengfei told reporters that the arc-shaped arch rib was closed on November 25. 802 rods of different lengths and types are arranged between the arch rib and the bridge deck, and they are hoisted and installed one by one in the way of "building blocks". In order to ensure millimeter-level closing accuracy, the builders have carried out a lot of research and development. For example, the use of the industry's largest tonnage WD100 arch crane to solve the problems of large-tonnage rod hoisting, steel truss girder winding walking, etc., the establishment of BIM-based digital twin construction scene, the construction of a cloud wireless collection system, all-round real-time analysis and early warning of construction control data, research and development of steel truss arch active closing technology, etc. It is worth mentioning that the steel consumption of the whole bridge of Tianxingzhou special channel bridge is about 40,000 tons, and the amount of high-strength bolts is about 470,000 sets, which is close to the total steel consumption of the Bird's Nest steel structure of the Beijing Olympic venues.
Keep improving, throughout the construction of Changtai Yangtze River Bridge. "During this year's construction, the precision control of the pillars on the main tower was more challenging. Xia Pengfei introduced, Changtai Yangtze River Bridge main tower is 350 meters high, is the world's highest cable-stayed bridge tower, the use of an unprecedented diamond-shaped structure, four tower limbs together "hold" into a tower column. "At that time, we set ourselves the inclination control target of H/8000, which is much higher than the verticality requirement of H/3000 required by the existing specification, but in the actual construction, through intelligent construction to achieve stricter quality control, continuous correction every day, and finally we achieved the capping of the main tower in September, and the verticality not only met expectations, but also exceeded expectations, far ahead in the industry. ”
At present, the main channel of the bridge is in the process of hoisting steel truss girders and installing cable-stayed cables in large sections, and it is expected that the closure will be realized in mid-2024 to ensure that it will be fully completed in the first half of 2025. Xia Pengfei said that as a bridge builder, he will continue to carry forward the spirit of the new era of "ingenuity casting, cohesion to build dreams" in the future, forge high-level bridges with intelligent management, and contribute to the road of transportation power.
Yangtze Evening News/Purple Cow News reporter Shi Xiaolei
Proofread by Li Haihui