LINING OF UNDERGROUND PRESSURE PIPELINE Russian patent published in 1994 - IPC

FIELD: construction of underground structures. SUBSTANCE: lining includes concrete layer annular in cross-section with reinforcement in form of nets. Concrete layer is separated in cross-section over its periphery into equal upper, lower and side parts. Reinforcement in lower and upper parts is multitier with bars spaced within their eight diameters, and in side parts, reinforcement is single-row its edges are brought into space between nets of multirow reinforcement at distance not in excess of 30 diameters of reinforcement bars. EFFECT: higher reliability of structure due to reduced level of value of crack opening in zones of reinforced concrete linings of tunnels not resistant to cracks. 1 dwg