Tunneliurakoneella

Tunneliurakoneella, commonly known as a Tunnel Boring Machine (TBM), is a piece of large mechanical equipment used to excavate tunnels through the ground. TBMs are designed to bore through a wide variety of geological conditions, from soft soil to hard rock. They operate by rotating a large circular cutting head at the front of the machine. This cutting head is equipped with numerous cutting tools, such as disc cutters and carbide bits, which grind away at the rock or soil.

As the TBM bores, it simultaneously installs the tunnel lining. This lining, often made of precast concrete segments, provides structural support to the newly formed tunnel. The excavated material, known as muck, is transported away from the cutting head through a conveyor system, which then disposes of it at the rear of the machine. Different types of TBMs exist, tailored to specific ground conditions and project requirements. Shielded TBMs offer protection to the workers and the freshly installed lining in unstable ground, while Main Beam TBMs are typically used in hard rock where stability is less of a concern. The use of TBMs allows for faster, safer, and more efficient tunnel construction compared to traditional drill and blast methods, especially in urban environments or beneath bodies of water. They are crucial for infrastructure projects like subways, water supply tunnels, and road tunnels.