What is the method of tunnel boring? Tunnel excavation refers to the construction process employed to dig tunnels under the ground or through mountains. The process of tunnel excavation encompasses several stages: first, geological exploration is conducted to understand the geological conditions along the tunnel route, facilitating the selection of appropriate excavation methods and equipment. Following this, the tunnel is excavated utilizing methods such as drill-and-blast, shielded tunneling, and Tunnel Boring Machine (TBM) techniques. Throughout the excavation phase, support structures and lining are installed to ensure the stability and safety of the tunnel. Additionally, auxiliary works such as ventilation and drainage are carried out to maintain suitable working conditions and ensure the proper functioning of the tunnel.
Here are some common methods of tunnel excavation:
1、Drill and Blast Method: This traditional method involves drilling holes, loading explosives, and blasting rock to break it apart, followed by muck removal and support installation. It is suitable for various geological conditions but can significantly disturb the surrounding rock, requiring strict support and monitoring.
2、Shield Tunneling Method: A mechanized approach, this method uses a tunnel boring machine (TBM) to excavate, support, and line the tunnel simultaneously. It is ideal for urban metro and underwater tunnels, offering fast construction speeds and minimal environmental impact.
3、Excavator Method: This method employs an excavator equipped with cutting tools to break rock and remove it from the tunnel. It is suitable for hard rock tunnels but has higher equipment costs.
4、Shallow Buried Method: Used in urban settings, this technique involves advanced support with small pipes, grid steel frames, and sprayed concrete for stable excavation. It is appropriate for busy city areas, minimizing surface disruption and environmental impact.
5、utility installations with minimal effects on surface traffic and the environment.
These methods cater to different geological conditions and project requirements. Careful selection and strict management are essential to ensure the safety and quality of the tunnel.