The Hangzhou Zhijiang Road Tunnel has been fully connected and successfully crossed the "highly sensitive" area

On October 10th, it was learned from the Hangzhou Municipal Commission of Housing and Urban-Rural Development that the tunnel of the Zhijiang Road Water Pipeline Corridor and Road Improvement Project (Zhipu Road - Fuxing Road), one of the "Thousand Projects Trillion Yuan" projects in Zhejiang Province, has been fully connected recently.

The project starts from Meiling South Road in the west and ends at Fuxing Road in the east, with a total length of approximately 6.3 kilometers. It serves as a crucial link between the Qiantang River and the West Lake Scenic area, and is also a key project for improving the three-dimensional transportation network and water network layout along the river in Hangzhou and ensuring people's livelihood.

The tunnel section is approximately 5.6 kilometers long. The main line shield machine needs to pass through various strata with uneven hardness. Not only are the geological conditions complex, but it is also adjacent to two world cultural heritage protection areas, namely the West Lake Cultural Landscape and the Hangzhou section of the Grand Canal of China. Along the way, it involves five key national cultural relics protection units, namely the former site of Zhijiang University, Liuhe Pagoda, Qiantang River Bridge, White Pagoda and Zhonghe River. It is one of the municipal tunnel projects with the strictest protection requirements and the greatest implementation difficulty in China at present.

The medium-weathered quartz sand in the hard rock stratum has a high quartz content, comparable to that of whetstone, and its strength is more than three times that of ordinary concrete. It causes great wear to the shield cutting tools, and the shield crossing poses a great challenge. The relevant person in charge of the project construction unit, Hangzhou Urban Infrastructure Construction Management Center, introduced that in order to ensure the smooth passage of the shield machine and the safety of cultural relics, the project team, in collaboration with research institutes, carried out geological research. They tailored a series of meticulous management measures, including real-time linkage of cultural relic safety monitoring and shield tunneling, for the shield machine's passage through various strata. On June 18, 2025, both shield tunnels of the main line were fully connected.

The first national-level cultural relic protection building successfully passed through the side of the project is the White Pagoda. The minimum horizontal distance between the Southern Tunnel and the White Pagoda is only 24 meters. The White Pagoda was built during the Wu-Yue period of the Five Dynasties period and has high requirements for cultural relics protection. However, the stratum of the shield tunneling section is full-section weathered quartz sandstone, and the construction vibration is prone to cause damage to the White Pagoda. The project team formulated a uniform passage and special monitoring plan to strictly control the shield tunneling parameters. According to the team's assessment, after the shield machine left the White Pagoda Protected Area, there were no abnormal changes in the structure of the White Pagoda.

The entire journey passes through three key nodes: the Qiantang River Bridge, the Liuhe Pagoda, and the former site of Zhijiang University, which poses extremely high requirements for deformation control. The project team strictly controlled deformation through measures such as pre-reinforcement, scientific research simulation, scientific construction, and real-time monitoring to ensure the safety of the Qiantang River Bridge, Liuhe Pagoda, and the former site of Zhijiang University.

The tunnel is set up with one pair of ramps on Zhijiang Road. The shield tunnel of the ramps needs to continuously pass through important transportation lines such as Zhijiang Road, Fuxing Road, and Metro Line 4. It also involves public welfare infrastructure such as the saltwater canal, the Middle River, the flood drainage channel, and the West Lake water diversion pipe. The strata in the crossing area are mainly silt and silt. In this stratum, the construction of ultra-shallow earth-covered shield tunnels is prone to the risk of floating. The project team, through research, formulated an anti-floating design and shield construction control technical plan for ultra-shallow soil cover large-diameter shield tunnels. They adopted the approach of "3-hour intensified monitoring + 24-hour manual inspection + establishment of an information linkage platform" to achieve low-impact and micro-disturbance construction, ensuring the normal operation of Metro Line 4 and the unaffected banks of the Zhonghe River.

With the successful reception of the ramp shield machine, the tunnel of the Zhijiang Road project has been fully connected. At present, the project has fully entered the construction stage of ancillary structures inside the tunnel, the laying of water pipes, mechanical and electrical installation, and decoration and renovation, to ensure that the tunnel is ready for traffic by the end of the year. After its opening to traffic, it is expected that the traffic capacity of Zhijiang Road will increase by 1.5 times.