Abstract: A device for opening and supporting a headway in closed or open excavations comprises an envelope composed of blade- carrying heads (24) which can be driven individually or in groups, each connected to an end part. At least several end parts are designed as internal formwork sections (12) and their top surface facing the ground or soil (26) slopes backward from the corresponding top surface (38) of the corresponding blade-carrying head. The blade-carrying head (24) and the end parts are supported and guided on supporting frames (16) of a walking frame (34). A filling tube (42) for introducing supporting material (44) and binders is arranged in the region between the blade-carrying head (24) and the sections (12) of the internal casing.

Abstract: A slide formwork with a formwork body (10) comprising several formwork segment groups (12, 22, 32) lying adjacent to one another in circumferential direction. Each of the formwork segment groups (12, 22, 32) is rigidly connected with one of several support frames (40) and is mounted onto the remaining support frames in slidable manner. Each formwork segment (14) comprises an outer formwork plate (16) supported on an associated longitudinal carrier (18) via hydraulic elements. The formwork plate (16) and associated longitudinal carrier (18) are coupled with one another in non-shiftable manner in longitudinal direction. Hydraulic presses (52) are arranged between the individual support frames (40), with which each support frame is shiftable with respect to the remaining support frames.

Abstract: The knife-shield driving device consists of drive knives (10, 12, 14, 16, 18) which can be acted on via a pushing device and are guided with respect to each other on their longitudinal sides. The guides consist of guide yokes (20) and wedge elements (30) which are guided in said guide yokes (20). For the change in direction of the driving it is sufficient to select any desired suitable guide knife (14) which is controlled in direction during the driving via hydraulic presses (34, 36) arranged on the adjacent knives (12, 16). In this connection, the guide yoke (20) slides on the wedge element (30) of the adjacent knife (12) and the wedge element of the knife (14) slides in the guide yoke on the knife (16).