Abstract: In a stressing anchorage for prestressing elements (2) in part of a structure, at least one part of an anchor head (4) consists of a mortar-like mass in the area in which bores (3) are disposed to accept frustoconical wedges (8). The frustoconical wedges (8) are made of steel. Since the mortar-like mass on which the frustoconical wedges are supported is more ductile, i.e., more workable than the wedges (8), the distribution of load from the wedges (8) to the anchor head (4) takes place in such a fashion that marked peaks of the load are considerably reduced.

Abstract: The force transfer body comprises a first, essentially annular partial body, preferably of cast steel, and a second partial body, preferably of a castable mortar mass capable of hardening. The second partial body is cast in one piece with the first partial body. An inner conical aperture is lined with a funnel-shaped plastic part, which overlaps at least a section of the first partial body. The first partial body has an abutting surface, turned away from the part of the structure, serving the firm contact with an anchor head containing individual members. The prestressing forces arising concentratedly with the anchorage are conveyed from the anchor head via the first partial body into the second partial body, and from there into the part of the structure. The second partial body is designed essentially frustoconical, the truncated cone extending, tapering, away from the first partial body. In the area of the outer generated surface of the second partial body there is a circumferential constriction.

Abstract: Each of the prestressing tendons (3, 4, 18) in a pressure tunnel is made up of a bundle of monostrands (21) held together. Each of the monostrands (21) of one of the prestressing tendons is distanced from adjacent monostrands by the introduction of spacing means (22, 22', 22", 22"') at more or less regular intervals along the length of the prestressing tendon. Distributed along the length of and over the circumference of the pressure tunnel are disposed prestressing tendon supports (9) directed essentially towards the center of the pressure tunnel. Several prestressing tendons (3, 4, 18) are attachable to each of the prestressing tendon supports (9) adjacent to or stacked on top of each other. In doing so, each prestressing tendon (3, 4, 18) is kept spaced from adjacent tendons. The prestressing tendon arrangement ensures that after concreting the pressure tunnel, each of the monostrands is completely embedded in concrete.

Abstract: The prestressed concrete lining has several reinforcement elements (32) distributed around the circumference and along the length of the pressure tunnel. There are prestressing elements (38, 39, 40, 41) which encompass at least a part of the circumference of the pressure tunnel. A bottom part (35) is disposed within the pressure tunnel, formed of several elongated anchorage bodies (15) in series. Each of the anchorage bodies (15) has an essentially U-shaped cross section. In each of the arms (2, 3) of the anchorage bodies turned towards the inside of the tunnel there are first means (5) for passing through at least one of each of the prestressing elements (38, 39, 40, 41). An bearing plate (8) is disposed on each of the facing inner surfaces of the arms in the region of each of the first pass-through means (5). Second means (10) for passing through at least one of each of the prestressing elements (38, 39, 40, 41) are foreseen in the base arm of the anchorage body 15.

Abstract: The wall (5) of the encasing tube (1) includes spiralling protrusions (3, 4). First protrusions (3) and second protrusions (4) run either in different directions or in the same direction but at different pitches. The encasing tube is used for enclosing tensioning cable (2) in concrete structures. By means of the particular arrangement of the protrusions, the flow properties of the grout are improved, air bubbles are virtually eliminated during injection, and the bonding properties of tensioning cables are improved by means of large bonding zones while respecting the required high fatigue strength.