Media Focus | New Progress of the "Super Project" of Xixiang Expressway! The pouring of the pier foundations on both sides of the Lugu Lake Special Bridge has been completed

On March 29th, the main tower foundation of the Shangri-La Bank of the Lugu Lake Special Bridge, constructed by the Bridge Branch of the Road and Bridge Group, was successfully poured, marking the completion of the pouring of all foundation foundations on both banks of the bridge and ushering in a new stage of construction.

The Lugu Lake Special Bridge is one of the "Nine Super Projects" of the Xixiang Expressway. It is located in Changbai Town, Yanyuan County, Liangshan Yi Autonomous Prefecture, Sichuan Province, spanning the Woluo River. It is a double-tower single-span steel truss girder suspension bridge with a main span of 1,680 meters. The bridge site area on the Shangri-La Bank is at an altitude of approximately 2,300 to 2,600 meters. The tower area is in a mountainous environment, facing unfavorable factors such as high altitude, fast wind speed and large temperature differences, making the construction extremely difficult.

To reduce the risk of the bridge structure being damaged by earthquakes, the 9-meter-high pier cap on the Shangri-La Bank adopts a "ring-shaped" design, which can not only steadily support the nearly 300-meter-high tower but also save concrete compared with traditional structures. Meanwhile, high-strength and low-relaxation steel strands are pre-embedded along the transverse direction of the bridge inside the foundation. This prestressed technology is like installing "springs" on the concrete, enabling the foundation to maintain its best shape even when subjected to loads of tens of thousands of tons.

To address the challenges such as the special structure of the foundation, the large volume of concrete pouring, and the high control requirements for the hydrothermal reaction (heat released when substances combine with hydration) of large-volume concrete, the construction team made early plans and arrangements. They used high-strength C40 concrete to pour in four layers, with a total pouring volume of 18,759.0 cubic meters. Based on BIM technology, an intelligent temperature control system for large volume concrete was developed. Compared with the traditional automatic timed temperature monitor, this system can wirelessly transmit data, automatically regulate and manage the flow of cooling water pipes, and visualize the data results. It precisely controls the inlet and outlet water temperatures in response to the hydration heat phenomenon, improving the pouring quality of large volume concrete while Effectively save labor costs.

The Lugu Lake Special Bridge, as a core component of the Xixiang Expressway, is the only way to reach Lugu Lake, Shangri-La and Muli Tibetan Autonomous County. After the bridge is completed, it will open up a convenient passage to Lugu Lake, significantly improve the regional transportation situation, further promote the economic and social development of the areas along the line, and effectively promote regional economic integration.

Extended reading

As a key project of the "14th Five-Year Plan" for building a strong transportation nation in China (Jiaoban Planning [2022] No. 21), the Xixiang Expressway is a section of the G7611 National Expressway from Duyun to Shangri-La and an important part of the Greater Shangri-La Tourist Ring. It is one of the most important east-west expressway channels in Yunnan, Guizhou and Sichuan provinces, and also a convenient connection between the Panxi Economic Zone and neighboring provinces. Open up the main economic trunk lines and major entrance and exit highway passages for external channels.

The Xixiang Expressway is located in the resource-rich Liangshan area. It is an important supporting project for Sichuan Province to build a strong transportation province and for the Sichuan Road and Highway Group to practice green and low-carbon construction. It is also the first demonstration project of the Sichuan Road and Highway Group to promote the integration of transportation and energy. After the project is completed and put into operation, it will end the history of Yanyuan County and Muli County having no expressway. It is of great significance for improving the transportation conditions in ethnic minority areas, consolidating and expanding the achievements of poverty alleviation, and promoting the development of regional advantageous resources and economic and social development.