The north main tower of the world's largest-span road-rail double-deck cable-stayed suspension cooperative system bridge — the Hubei Jingzhou Libu Yangtze River Road-Rail Bridge — has recently completed tower base construction and entered the full-scale main tower construction phase.

The Hubei Jingzhou Libu Yangtze River Road-Rail Bridge enters the main tower construction phase

　　The Jingzhou Libu Yangtze River Road-Rail Bridge is located in Jingzhou District, Jingzhou City, Hubei Province, with Libu Town of Jingzhou City on the north bank and Mishi Town of Jingzhou City on the south bank. The bridge has a total length of about 7.9 kilometers, and the river-crossing main bridge is 1,723 meters long. The lower deck carries a double-track high-speed railway and a four-lane urban road, while the upper deck carries a six-lane expressway, making it a river-crossing corridor integrating high-speed railway, expressway and urban road. To avoid piers entering the river and affecting the ecological environment and to protect biodiversity in the Yangtze River basin, the main bridge adopts a single-span river-crossing construction scheme.

　　According to Wang Ping, chief engineer of the Jingzhou Libu Yangtze River Road-Rail Bridge project of China Construction Third Engineering Bureau on the north bank, the Libu Yangtze River Road-Rail Bridge is not only China's first steel truss cable-stayed suspension cooperative system bridge with a main span exceeding one kilometer, but also the world's largest-span road-rail double-deck cable-stayed suspension cooperative system bridge, featuring the engineering characteristics of "three new and four high."

　　Specifically, the structure is new: the bridge adopts a cable-stayed-suspension cooperative system; the equipment is new: the north bank cable tower construction uses the 2.0 version "tower-building machine" newly developed by China Construction Third Engineering Bureau, which features lightweight multi-point hierarchical support, a high-turnover assembled integral adaptive platform, and integrated intelligent construction system functions; the technology is new: the cantilever erection of the main girder in the cable-stayed portion of the main bridge and the erection of the main girder in the suspension section are carried out simultaneously, making construction alignment control highly difficult.

　　At the same time, construction standards are high: the lower deck has a double-track railway in the middle, built to high-speed railway standards, and two-way four-lane urban roads on both sides, built to first-class highway standards — a standard that ranks first in the world among similar bridges; the bridge has high requirements for key technologies such as main cable alignment control, manufacture and installation of stay cables and hangers, and segmental hoisting of the steel truss girder; due to complex geological conditions, pile foundation hole formation requires passing through fine sand, silty sand and gravel layers, imposing high requirements on construction quality; the main girder adopts a Warren truss structure, with a truss height of 14 meters, a truss width of 38.6 meters, a maximum single segment length of 32 meters and a maximum single piece weight of more than 1,700 tonnes, imposing high safety requirements on steel truss girder hoisting.

　　Both main tower piers of the bridge adopt bored pile foundations. The north main tower is located on the north bank beach, is 215.5 meters high, and uses 90 bored cast-in-place piles with a diameter of 2.5 meters arranged in a grid pattern. Tower base construction has now been completed, and the top surface of the tower base has exceeded the average Yangtze River water level. Capping is expected to be achieved next year.

　　It is understood that the Jingzhou Libu Yangtze River Road-Rail Bridge is a control project for the southward extension of the Jingmen-Jingzhou Railway, the Jingzhou urban section rerouting of the Erenhot-Guangzhou Expressway, and the Jingzhou urban road network. It is of great significance for improving the backbone road network structure of the Yangtze River Economic Belt, enhancing flood control and rescue capacity in the Jingjiang flood diversion area, promoting cross-river integrated development of Jingzhou, and facilitating Jingzhou's efforts to build a regional central city in central Hubei.