lvzhijiang Bridge Created Three "World’s No.1"

lThe first steel box girder suspension bridge with single tower and single span 

in the highway construction in the world

lMain span 780m

lThe maximum inclination of tunnel anchor - 54 degrees

Lvzhijiang Bridge is a key project of Yuchu Expressway. It is located at the junction of Yimen County and Shuangbai County, and crosses Lvzhijiang river. The bridge has a total length of 798 meters. It is a two-way four lane bridge with a design speed of 100 kilometers per hour. Both banks are directly connected with the tunnels. The steel girder of the bridge is divided into 61 sections. The total weight of the steel box girder is about 10000 tons, which is equivalent to an Alfie tower. The maximum lifting weight of a single section exceeds 180 tons.

 New Construction Method of Steel Beam

The height difference between the bridge deck and the assembly yard is 320 meters, which is about 100 floors high. Especially for the No. 27 beam section on Chuxiong bank, the difficulty of hoisting and installation method is rare in China. In order to ensure the completion of the steel beam erection task on schedule, the construction team of China Railway Major Bridge Engineering Group keeps the construction spirit of "high starting point planning, high standard construction and efficient construction", scientifically organizes fine and high-quality construction, specially designs and optimizes the special lifting appliances for cable crane and catwalk system. During the erection process, the project team strictly used the "one lifting and one inspection" method, and carried out grid monitoring and control at each position of steel box girder hoisting to ensure the accuracy of the alignment and position of steel box girder. To solve the problem of sliding erection in the tunnel, the builders creatively adopted the method of longitudinal auxiliary traction and crown block following traction in combination with practice, and took many measures to ensure the safety and efficiency of steel beam erection.

Intelligent Bridge Construction

Technological construction method and management innovation have also played an important role in bridge construction. It is understood that since entering the construction site in 2019, the project builders have actively practiced the concept of safe, civilized, green and environmental protection construction, implemented scientific management modes, and built facilities such as "safety Podium" and "VR safety experience room", which have overcome many problems.

The inclination angle of the bottom plate of the anchor plug body of Yuxi'an tunnel is up to 54°, the amount of mucking is large, and the construction period is tight. Under severe construction environment, a set of intelligent mucking equipment and multi-layer main body cross construction method were independently developed. By the system of construction method cooperates with the construction method, the excavation and construction of a single Yuxi'an tunnel anchor takes only 4.5 months. The construction method of "rapid mucking construction of large inclination tunnel anchor" and the patent of "a construction method of large capacity and rapid mucking of large inclination tunnel anchor" have been formed, which will be applied to the construction of plateau railway.

Yuchu expressway is a very important part of Guangzhou Kunming Expressway and an important part of Yunnan Expressway Network, with a total length of 190.597 km. After the completion of the project, the period of no Expressway in Shuangbai County, Chuxiong Prefecture will be ended, and the interconnection of surrounding counties and towns will be realized. The traffic time on both sides of the bridge will be shortened from the original 1.5 hours to 2 minutes, which will greatly improve the counties and towns on both sides of the bridge, promote the traffic and economic exchanges in the surrounding areas, improve the investment environment, open up a fast channel for the people along the line to increase income and become rich. It will promote the tourism development and development of central Yunnan Economic construction plays an important role.