A tunnel boring machine (TBM) is a specialized piece of heavy equipment used for excavating tunnels with a circular cross-section through a variety of soil and rock conditions. These machines, available for purchase on the market, come in various sizes and configurations to suit different project requirements, from small-diameter utility tunnels to massive transportation infrastructure projects. The availability of used TBMs offers a potentially cost-effective alternative to new machines.
Mechanized tunneling offers significant advantages over traditional methods, such as drill-and-blast, by enabling faster excavation rates, improved worker safety, reduced surface disruption, and more precise tunnel construction. The acquisition of a TBM represents a substantial investment for infrastructure projects, potentially shortening project timelines and minimizing environmental impact. The history of these machines dates back to the early 19th century, with continuous advancements in technology leading to the sophisticated TBMs available today.