tunnelikoneissa

Tunnelikoneissa is a Finnish term that translates to "tunnel excavators" or "tunnel boring machines" (TBMs) in English. These are large, complex mechanical devices used to excavate tunnels through a wide variety of geological conditions. TBMs are a relatively modern innovation in tunnel construction, offering a more controlled and often faster method compared to traditional drill and blast techniques.

The primary function of a tunnelikone is to bore through the ground, creating a circular opening of a specific diameter. The cutting head of a TBM is equipped with rotating cutters that break apart the rock or soil. As the machine advances, it simultaneously installs a lining, typically made of precast concrete segments, to support the excavated tunnel walls. This process ensures stability and prevents collapses.

Tunnelikoneet come in various types, designed for different ground conditions. Soft ground TBMs are suited for unconsolidated materials like sand and clay, while hard rock TBMs are built to withstand the stresses of excavating through solid rock. The choice of TBM depends on factors such as the geology of the intended tunnel path, the required tunnel diameter, and the project's budget and timeline. Their use has revolutionized urban underground construction, facilitating the creation of subways, water tunnels, and utility conduits with greater efficiency and safety.