Method of constructing an extended free chamber between two tunnel segments

摘要

Process for creating an elongated free space (1) between two tunnel tubes (2, 3) comprises constructing two parallel tunnel tubes separated from each other by a central region, and inserting reinforcing devices perpendicular to and between the tunnel tubes. The reinforcing devices are used to reinforce an arched roof region (17) above the not yet opened central region. The central region is then opened below the reinforced arched roof region. Preferred Features: The arched roof region is reinforced using iron. The central region below the arched roof region is opened by at least one tunnel tube. The opened central region is protected by an upper sprayed-concrete shell (19).