A tunnel boring machine is a mechanical device used for underground construction projects, specifically designed for efficient tunnel excavation. It works by breaking up rocks or soil with a rotating cutting head, thereby excavating the tunnel. A TBM mainly consists of three parts: the cutting head, the body, and the propulsion system. The cutting head is equipped with multiple cutting tools, such as disc cutters, breakers, and drill bits, used to directly break up rocks or soil. The body contains motors and hydraulic systems to provide power and control. The propulsion system is responsible for pushing the machine forward, which can be mechanical or hydraulic.
During the tunneling process, the TBM's cutting head rotates to cut through rocks or soil, and the debris is discharged outside the machine through a conveying system. Meanwhile, the propulsion system pushes the machine forward to continue the cutting operation. TBMs are also equipped with guidance and measurement systems for precise control of the tunnel alignment and dimensions.
Depending on the tunneling method, TBMs can be divided into various types such as open-type, shield-type, and hybrid-type. Open-type TBMs are suitable for hard rock tunneling, shield-type TBMs are suitable for soft soil and weak strata tunneling, while hybrid-type TBMs combine the advantages of both open-type and shield-type TBMs and can adapt to various complex geological conditions.
TBMs have a wide range of applications, including tunnel construction, mining, hydraulic engineering, urban rail transit construction, and more. With advancements in technology and engineering, modern TBMs are becoming increasingly advanced and have become indispensable equipment for tunnel and underground construction projects.
The design and scale of TBMs vary depending on specific engineering requirements. Some can be operated by personnel, while others use remote control or automation technology. These machines typically have strong excavation capabilities and can operate in various geological conditions.