After 597 days, another victory! On October 12, the left tube of the Lishuwan Tunnel on the C1 section of the Chongqing Wuyun-Kai Expressway, constructed by CCCC Road & Bridge Construction Co., Ltd., was successfully holed through, marking the full-bore breakthrough of the tunnel.

"The smooth breakthrough of the tunnel on schedule would not have been possible without the support and cooperation of the First Brigade of the Engineering Quality Supervision Detachment of the Chongqing Municipal Transportation Comprehensive Administrative Law Enforcement Corps, which greatly encouraged and boosted the confidence of the project construction personnel. Next, the project will continue to ensure safety supervision, quality control, and environmental protection requirements, and persistently advance project construction with high quality, high standards, and strict requirements," said project manager Ding Zhigang.

According to Lü Xiaoping, deputy production manager of the project responsible for the construction of this section, the Lishuwan Tunnel is located in Yunyang County, Chongqing. Its entrance lies in the mountains near Fanjiagou. The left tube is 1,747 meters long, the right tube 1,712 meters long, and the maximum burial depth is about 256 meters. The tunnel is situated in a tectonic erosional landform characterized by crisscrossing ravines and developed vegetation. The surrounding rock is complex and variable, dominated by Grade IV and V rock, and passes through unfavorable geological conditions such as fault fracture zones, weak interlayers, seepage in rock strata, and densely jointed zones. Far from towns and off the main traffic arteries, the roads are narrow, steep, and winding, making the supply of personnel and materials difficult and construction operations highly risky and challenging.

Faced with such harsh and difficult construction conditions, the project formulated targeted construction plans, abandoned the traditional manual operation model, and adopted an operating model of "mechanization replacing manpower and intelligentization reducing manpower." By introducing advanced equipment, it increased the use of machinery and equipment such as multifunctional advanced geological drilling rigs for exploration and forecasting, two-boom rock-drilling excavation jumbos, systematic rock bolt drilling rigs, multifunctional arch installation trolleys, and wheeled wet-spraying robotic arms, thereby reducing manual work, easing workers' labor intensity, and ensuring on-site construction quality and progress. Through technological innovation and the application of new materials, the project greatly improved engineering safety while reducing the consumption of raw materials. By building a "smart construction site," it was able to grasp construction difficulties and other issues through visual models, ensuring construction safety while greatly improving construction efficiency.

It is worth noting that despite the tough engineering conditions, the construction unit still adhered to the low-carbon concept, promoted electrification and emission reduction, and focused on protecting the local ecological environment, making the greatest effort to minimize disturbance to the environment and prevent damage to water sources and mountain vegetation, thus advancing green construction.

At the construction site, workers were methodically clearing blast rubble inside the tunnel. The tunnel, not yet fully completed, had already begun to take on an unobstructed appearance. "Two years, nearly 600 days—truly countless sleepless nights in the tunnel! We finally succeeded!" Members of the on-site project team exclaimed with deep emotion, unable to hide their excitement.

"The tunnel is through, and the road will soon be through too. Once the expressway is fully completed, we'll be able to get to the county town much faster—from the original hours-long journey over rugged mountain roads to just about ten minutes, fast and convenient. Life will keep getting better!" Facing the breakthrough of the Lishuwan Tunnel, a local resident could not help but envision the future.

It is understood that the Wuyun-Kai Expressway belongs to the 33rd link of the "Three Rings, Eighteen Radials, and Multiple Connectors" of the Chongqing expressway network and is a major municipal project of Chongqing. The project starts in Wuxi County, Chongqing, passes through Yunyang County, and ends in Kaizhou District, with a total length of 118.62 kilometers. The entire line features 86 bridges and 21 tunnels, with a bridge-to-tunnel ratio of 60%. The design speed is 80 km/h, with four lanes in both directions. The C1 section constructed by CCCC Road & Bridge Construction Co., Ltd. has a route length of 15.32 kilometers, and its construction scope includes subgrade, bridges, tunnels, and hub interchange works.

After the project is completed, it will be of great significance for accelerating the development of tourism resources in Hongchiba and along the route, promoting the development of the urban agglomeration in the Three Gorges Reservoir Area of northeastern Chongqing, improving regional traffic transfer and traffic capacity, and helping rural revitalization in areas along the route and driving local economic and social development.