China News Service, Yichang, September 9 (Li Huixi, Yu Zhe) The pouring of the main pier caps on the north bank of the Yichang West Expressway Three Gorges Bridge, invested and constructed by Hubei Communications Investment Group and constructed by China Communications Construction Company Second Harbor Engineering Company, was successfully completed on the 9th.
On September 9, the pouring of the main pier cap on the north bank of the Yichang Three Gorges Bridge was successfully completed. Photo courtesy of CCCC Second Harbor Engineering Company
Yichang West Expressway starts from Xiaoxita Street in Yiling District, connects to the G42 Shanghai-Chengdu Expressway, and ends in Gaojiayan Town, Changyang Tujia Autonomous County. It connects to the G50 Shanghai-Chongqing Expressway. The total length of the line is 46.997 kilometers, and the entire line is constructed to a two-way six-lane standard. Among them, the Three Gorges Bridge is a key control project for the entire line. It is located at the mouth of Xiling Gorge between the Three Gorges Dam and Gezhouba Dam. The upper layer is a two-way eight-lane expressway, and the lower layer is equipped with a slow-travel sightseeing system. The main span of the bridge is 1,200 meters, the width is 42.6 meters, and the bridge deck is 270 meters away from the river. It is currently the largest double-layer steel truss-UHPC deck composite girder suspension bridge in China. It is also the widest steel truss girder suspension bridge on the Yangtze River and the first integrated bridge and brigade bridge in Hubei Province. It was selected as a demonstration project of the Ministry of Transport to build a powerful transportation country.
The main pier cap on the north bank of the Three Gorges Bridge is a separate cap with pile group foundation structure. The dimensions of the left and right caps are 26.2 meters long, 26 meters wide and 8.5 meters high. The designed pouring volume is 5790.2 cubic meters. The bridge's main pier cap is located in the Xiling Gorge Linjiang Canyon area, where the temperature difference between day and night is large. Temperature cracks are easily produced during large-volume concrete pouring, which places extremely high requirements on pouring technology, temperature control maintenance and construction continuity. At the same time, the concrete tank trucks need to pass through the G348 Three Gorges Tourist Highway, and the concentration of traffic makes it difficult to ensure access; the project is close to the Yangtze River Ecological Control Zone, and the environmental standards for soil and water conservation and sewage disposal are strict.
Faced with multiple construction problems, the project department set up a special technical team to optimize the construction plan based on on-site geological and hydrological conditions, using layered pouring and zoned vibration techniques to accurately control the concrete ratio, pouring speed and vibration density. The project introduces an intelligent temperature control monitoring system to track the temperature changes inside and outside the concrete in real time. Ice-making technology is used to reduce the temperature of the concrete entering the mold. It is combined with layered insulation and watering maintenance to effectively prevent cracks. At the same time, we adhere to the bottom line of green construction in the Yangtze River. The construction site is equipped with an integrated mud and sewage disposal station. Construction waste residue and discarded building materials are transferred in a centralized manner. The bare soil is fully covered to suppress dust, minimizing the disturbance to the Yangtze River waters and surrounding mountain vegetation.
After the completion of the Three Gorges Bridge, it will complete the closed-loop channel of the Yichang Ring Expressway, close the urban expressway network from a "C" shape to a complete "O" shape loop, optimize the layout of the Yangtze River crossing channel, improve the Three Gorges regional comprehensive transportation network, strongly support the implementation of the national major strategy of the Three Gorges Water Transport New Channel, and have far-reaching significance for the improvement of Yichang's overall transportation quality and the integrated development of culture and tourism.
