TUNNEL SHIELD Russian patent published in 2002 - IPC

FIELD: underground construction. SUBSTANCE: invention refers, in particular, to construction of tunnels with use of tunnel shields with slip forms and can find use in building of underground of poured-in-place, pressed concrete. Tunnel shield has frame, forming section of slip forms joined to frame of shield, intermediate sections of forms and supporting section. Face surface of intermediate sections and supporting sections are made spherical and are put on longitudinal axis of shield for turning along surface of sphere. Unit joining sections of forms comes in the form of flexible cable reeved off in roller blocks and anchored so that its tension can be adjusted. One group of roller blocks is anchored on internal surface of forming section and another group is anchored on internal surface of supporting section. Said groups are intercoupled by common reeved off flexible cable. Each intermediate section and supporting section are made of segments built-up in radial direction, trapezoidal wedges being installed between them. They are mounted with the use of springy members on internal surface of each section. EFFECT: increased functional reliability and quality of lining of underground structure. 5 dwg