Dyckerhoff & Widmann Aktiengesellschaft

Other

Oswald Nutzel

Dieter Jungwirth

Egbert Zimmermann

Johann Wlodkowski

Lorenz Schnitzler

Werner Hansch

Christoph Nieberle

A method of mounting and tensioning a freely tensioned tension member, particularly a stay cable for a cable-stayed bridge, and a device for carrying out the method, wherein the polyethylene casing of each individual strand is removed during the tensioning process over the length of the extension distance occurring during tensioning at the tensioning end. The peeling tool of the device for carrying out the method is composed of a sleeve having at one end thereof at least one cutting edge, wherein the sleeve surrounds the respective strand over at least an essential portion of the circumference thereof. The sleeve can be positioned in a stationary manner between the anchoring disk and the tensioning press, wherein the strand is pulled through the sleeve during the tensioning process.

Method of mounting and tensioning a freely tensioned tension member and

A sealing arrangement for closing off the areas to be filled with a casting compound of a tension member composed of a bundle of individual elements arranged within a tubular sheathing, for example, a stay cable of a cable-stayed bridge, includes a sealing plug composed of a first sealing layer of a deformable, non-flowable sealing material introduced between the individual elements, a second sealing layer of a setting or hardenable material introduced in a flowable state and arranged adjacent the first sealing layer in the direction toward the area to be filled out with casting compound.

Sealing arrangement in a bundled tension member for prestressed concrete

A device to be used in inserting the individual tension elements of a freely tensioned tension member, for example, a stay cable for a cable-stayed bridge, into a tubular sheathing. A guide element to be attached to the front end of an individual element includes an expansion member whose diameter in its non-expanded state corresponds approximately to the diameter of the individual element, while the diameter in the expanded state is greater than the diameter of the individual element.

Device for use in inserting individual tension elements of a freely

A method of introducing a casting compound composed of aggregates and a matrix with a hardening binder into a hollow space within a tubular sheathing of a tension member composed of one or more individual elements, particularly in the anchoring range of the tension member relative to a structural component. In accordance with the method, the aggregates are introduced first and the matrix is then introduced in the liquid state into the grain structure formed by the aggregates. A finely granular material is used as the aggregate. The finely granular material is introduced with the aid of compressed air through at least one tubular lance which is inserted in longitudinal direction of the tension member through the anchoring range.

Method of introducing a casting compound into a hollow space

A corrosion-protected tension member, such as a tendon for prestressed concrete with post-tensioning, is made up of a bundle of individual tension elements, such as strands, arranged within a tubular envelope. The tension member extends between anchoring devices, each forming an anchor region for the tension member with a free region located between the anchor regions. In the free region, the tubular envelope is formed of a sheathing tube. Each individual element is located within a separate sheathing duct, and a corrosion-protection mass fills the space within the ducts about the elements. The open volume within the sheathing tube around the sheathed elements is filled with cement mortar. In the anchor regions, the tubular envelope includes an anchor tube enclosing an anchor pot. The anchor pot has a base with openings through which the individual elements pass in a sealed manner. The anchor pot is filled with a corrosion-protection mass. Accordingly, the individual elements are axially movable and retensionable along their entire lengths. The sheathing ducts and the anchor pot separate the cement mortar from the individual tension elements in the free region extending between the anchor pots.

Corrosion protected tension member for use in prestressed concrete and

A tendon for use in prestressed concrete is made up of a plurality of individual elements such as strands of steel wire arranged in a uniform array around and spaced radially outwardly from a center point. A spacer for the tendon includes a star-shaped base formed by arms extending radially outwardly from a central part. The central part and the arms define triangularly shaped openings for receiving one or a number of the tension elements. An intermediate part is positionable within the triangularly shaped openings for separating the elements located within the opening. The intermediate parts have a radially extending web and a flange extending transversely of the web for dividing the opening into separate spaces for each tension element. During assembly, the base is inserted into the tension member for separating the tension element and then the intermediate parts are inserted for spacing the elements from one another. The spacers are intended for use at a change in direction point of the tension member and initially are assembled at a position spaced from the change in direction point and then are moved to the point.

Spacer for tension member

In the assembly of a tension tie member between spaced anchors when the tie member is made up of a number of individual tension elements, such as steel wires, steel strands or the like, enclosed within a tubular sheathing, the tension elements are inserted individually and successively between the anchors and it is necessary to insert the annular wedges which anchor each element before the tension elements are released from a threading device. To prevent the annular wedges from prematurely entering into the boreholes in the anchor plate, an auxiliary plate is positioned spaced from the anchor plate. The auxiliary plate has at least one through borehole axially alignable with the boreholes in the anchor plate. A tubular section is secured to the auxiliary plate and forms an extension of the borehole therein. An annular wedge to be inserted into one of the boreholes and the anchor plate can be held on the tubular section by resiliently expanding the wedge about the outer surface of the tubular section. An individual tension element can be inserted through the auxiliary plate and then through the anchor plate and the tubular sheathing and finally through the other anchor plate without any interference from the annular wedge. After the tension element is completely inserted, the wedge can be slipped off the tubular section and inserted into the borehole in the anchor plate by means of a simple handle.

Apparatus for and method of assembling a tension tie member

A tension tie member is anchored between two spaced locations on a structure, such as a diagonal cable in a stayed girder bridge. The tie member is supported on the structure adjacent at least one anchor location by an annular bearing member encircling an outer protective casing of the tie member. The bearing member is positioned within an annular chamber in the structure at the point where the tie member extends through the structure toward the anchor location. The diameter of the annular chamber is larger than the diameter of the tie member so that there is a certain amount of play between the bearing member encircling the tie member and the surface of the annular chamber whereby lateral movement of the tie member can occur. With the tie member anchored in place the space between the outside of the bearing member and the inside surface of the annular chamber can be filled with grout to support the tie member.

Support for a tension tie member, such as a diagonal cable in a stayed

In a recoverable form for use in the region where a tendon is anchored in a prestressed concrete component, a part is provided for forming a cup-shaped recess in the concrete surface. The part contains an axially extending passage through which a tendon extends. The part is formed of rubber or a rubber-like material and is constructed so that its outer surface extending in the direction of the passage arches outwardly away from the passage when a compressive force is applied to the part in the axial direction of the passage.

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Munich, Germany

Oswald Nutzel