On the 27th, the first PPP project in Liuzhou City, Guangxi Zhuang Autonomous Region, the Lianhuashan Tunnel on Lianhua Avenue, was fully completed, marking the completion of one of the few municipal roads in China that pass through the urban forest park.

Lianhua Avenue is the first of the top ten urban construction projects in Liuzhou City's "Thirteenth Five-Year Plan". It is located in Liuzhou, Guangxi, a typical karst landform area known as "construction forbidden area". Sanmenjiang National Forest Park, Lianhuashan Scenic Spot, known as "Oxygen Bar", has a total length of 5370.3 meters and a total investment of 1.6 billion yuan, including 2 tunnels, 2 interchanges, and 13 bridges. It is the project with the largest investment, the most difficult construction, the highest bridge-to-tunnel ratio, the greatest safety risk and the strictest environmental protection requirements in Liuzhou.

Lianhuashan Tunnel, a key and difficult control project of the project, has a total length of 1885 meters and is the longest municipal tunnel in the history of Liuzhou City. There are more than 60 different types of karst geology. On average, there will be a karst danger and emergency rescue every 60 meters. Such dense karst and difficulty in operation are described by the construction workers as "walking in the devil's zone" and "bathing in a natural sauna". In the hot, humid and sweltering operation, there will be dangerous claws sticking out at any time, and the danger of "choking the neck" will appear at any time.

In the face of danger, the project department firmly grasped the weapon of scientific and technological innovation. In order to safely and quickly pass through the karst development areas one after another, they changed the drill pipe shed to the self-rotating pipe shed for construction, and at the same time made a multi-functional excavation trolley, By adjusting the height hydraulically, the safety distance from the lining to the face is shortened, and the initial support settlement caused by the instability of the karst filling is controlled. Tunnel cross channel to increase the working surface and speed up the construction progress. At the same time, the construction team was scrambling for time and time to seize the construction period. Moreover, the application of BIM technology in the anti-collision of tunnel electromechanical pipelines won the third prize of the Guangxi Construction Engineering Cup. The research on the key technologies for the fully efficient construction of extra-large cross-sections in the deep rock development area summarized during the construction was successfully applied for the Autonomous Region Science and Technology Award. .

At present, Lianhua Avenue is advancing in an orderly manner according to the landscape engineering standards of "adding green to the city, making the "green lungs" evergreen, and integrating with the forest". The tunnel landscape decoration is in full swing, and the top decoration is intelligentized by spraying and lighting. Control, so that the top of the tunnel presents a scene of bright starry sky and blue sky and white clouds.

After the Lianhua Avenue project is put into operation, it will become a fast passage connecting Liuzhou Hedong District and Liudong New District, allowing citizens to travel with the blue sky and white clouds, accompany with green water and green mountains, and enjoy the natural beauty of the southern country. By then, the increasing traffic pressure on Guiliu Road and Sanmenjiang Bridge will be greatly relieved, and the time for citizens to travel from the East Area to Liudong New Area will be shortened from more than one hour to about 10 minutes by car. (Guangming Fusion Media reporter Zi Qian, correspondent Zhu Guocai)