On the morning of May 12, the Shenxianling Tunnel, a controlling project of the Charao Expressway, officially began tunnel excavation, marking that the project's tunnel works have fully shifted into the tunnel body operation stage.

The main line of the Charao Expressway starts at the Chating Interchange of the Xuguang Expressway (Yuewang Section) and ends at the Laodaohe Hub Interchange, connecting with the Changsha Ring Expressway, with a total length of about 23.163 kilometers. It is the first expressway in the province to be superimposed with urban municipal roads. The main line is built to the standard of a two-way six-lane expressway, with a design speed of 120 km/h and a subgrade width of 34 meters. The project is wholly invested and constructed by Hunan Construction Investment Group, and its subsidiary Hunan Chajiang Expressway Construction and Development Co., Ltd. is responsible for construction, operation and management.

The Shenxianling Tunnel is located at the junction of Qiaoyi Town in Wangcheng District and Qingzhuhu Subdistrict in Kaifu District. It is a long two-way six-lane expressway tunnel arranged in separate left and right tubes, with the left tube 703 meters long and the right tube 735 meters long. The geological conditions in the tunnel area are complex, covering Grade III, IV and V surrounding rock, of which Grade V surrounding rock accounts for nearly half and is interspersed with fault fracture zones. The tunnel entrance is adjacent to a petroleum pipeline of the National Pipeline Network, and the exit section involves the protection of 500KV and 110KV high-voltage towers, with multiple ponds and ascending springs distributed in the area. Construction safety risks are high and control is difficult, making it a key controlling project of the entire line.

In response to difficulties such as frequent switching of construction methods for different surrounding rocks and adjacent construction near the petroleum pipeline and high-voltage towers, the project has adopted comprehensive measures including dynamic optimization of construction methods, non-explosive excavation, surface grouting reinforcement, outward expansion of foundation underpinning pile foundations, and high-frequency monitoring and early warning, to ensure construction safety and the stability of surrounding facilities. At the same time, mechanized and intelligent tunnel construction is fully promoted, with complete sets of equipment such as arch installation trolleys and automatic shotcrete robotic arms, implementing the management approach of "replacing workers with machinery, reducing workers with automation, and improving quality with intelligence," effectively enhancing construction precision and efficiency.

Once the Shenxianling Tunnel is completed, it will further shorten the distance between the Hedong area of Wangcheng District and the central urban area of Changsha, and continuously optimize the regional road network structure. In subsequent construction, the project team will closely monitor the site, strictly control details, and steadily advance operations such as tunnel body excavation and lining support, ensuring the project is completed and opened to traffic on schedule.

Source:Changsha Evening News