DE102008044918A1 - Coupling sleeve for cleansing coupled anchor for strand clamping method with connection for inserting in engineering work, e.g. bridge and tower, has standard force-locked construction for connecting two sheathed tendons - Google Patents

Abstract

The coupling sleeve has a standard force-locked construction for connecting two sheathed tendons. The two half-wrapped coupling sleeve bodies are mounted according to assembly of the standard coupling body, and the systematic coupling of a cycle stage construction is clamped in the coupling sleeve body, so that the connection of further coupling anchors body is provided.

Description

coupler anchor for strand tensioning with afterthought Composite serve to connect continuous tendons z. B. in bridge structures. They will be technically necessary if the building is in several stages will be produced. You can also manufacturing technology required, if the possible Clamping lengths exceeded become.

Of the Coupling anchor is essentially characterized by the constructive possibility the non-positive Connection of stranded wires. These are generally guided by conical holes in the coupling anchor body and by means of conical wedges, after introduction of the biasing force, positively connected.

If now this scheduled connection option is not feasible, becomes the load-bearing structure of the building endangered.

Of the specified in claim invention, this problem is based.

The particular advantages of this invention are that a continuous continuation of construction without significant Interventions in the already completed components is possible. The coupling elements can are manufactured under industrial standards and are thus subject not possible construction site influences. The work on the overall project can Continued without interruption become.

One embodiment is shown in the accompanying drawing. Also attached is the static verification.

A Further application of the invention lies in the possible conversion of fixed or clamping anchor heads in a coupling anchor.

2.3 Consideration to coupling anchor B10 between 1st and 2nd BA

2.3.1 Starting position:

At the Pressing the tendons of the 1st BA were accidentally drilled for the 2nd stranded strands to be coupled in the anchor body of 1st BA completely sealed with grouting mortar. Thus, the existing there ring wedges and springs are useless. Trying to reopen the holes and clean all parts, was not taken because of the uncertain result.

in the Order of the pretensioning company SPANKERN will therefore be an additional coupling sleeve designed and proven, with the necessary forces between the clamping bundles B7 (1st BA) and B10 (2nd BA) become. Likewise, the changed Stress of the coupling anchor body considered.

Cut F-F M 1:50

Ausschnitt aus Spanngliedplan 471a

Section of tendon plan 471a

Ausschnitt aus der Detailzeichnung der Fa. BBR (Zulassung ETA – 06/0147), Feste Kopplung Typ K: 1. BA links

Detail from the detail drawing of the company BBR (approval ETA - 06/0147), fixed coupling type K: 1. BA left

2.3.2 Remediation solution:

By the installation of an individually manufactured coupling sleeve should the coupling of the two tension strands respectively. This will be a welded construction Made of S 355 J2G3, which in two halves the old, partly unusable, with a new anchor body connects. In the area The old anchor is to slightly truncate the armor plate.

Sanierungslösung: Horizontalschnitt

Remediation solution: Horizontal section

Sanierungslösung: Querschnitt A-A (Prinzip, genaue Angaben siehe zugehörigen Plan)

Remediation solution: Cross-section AA (principle, for details see related plan)

The coupling sleeve becomes two halves as shown made, over guided the existing anchor and, after the extra anchor body and the spacer ring are inserted, bolted. After the screwing can the strands of the 2nd BA normal with the existing ring wedges on the outer bolt circle of the additional anchor body anchored. In the front of the coupling sleeve, the blind holes for attachment the trumpet (cladding) analogous to the hole pattern in the anchor body produced. At the high point of the coupling sleeve is a hole as a vent (with Hose connection) made to complete a compression of the cavities after to the auditing of the 2nd BA.

The tensile forces are introduced at both ends by pressure contact in the anchor body. The screw connection of the two halves the sleeve done for structural reasons, in the compressed state, all unscheduled transversely directed forces such as also the ring pull forces taken up by the concrete.

The Glued on the front side elastomer layer ensures that the coupling sleeve when prestressing can stretch (elongation less than 0.5 mm), without the prestressing force settles directly on the concrete of the 2nd BA. In order to it can not come to the decompression of the coupling joint, the evidence in the superstructure science stay valid.

Evaluation of the stress calculation for the coupling sleeve:

The maximum main tensile stresses under the characteristic tensile force of the tendon are about 396 MPa, the maximum main compressive stresses about 360 MPa (both in the ring disk). The characteristic breaking strength of the used steel S 355 is 510 MPa (with pipe from E 355 490 MPa).

The maximum working load of the tendon on the coupling anchor is 4.05 · 1292 · 0.632 = 3307 kN (see page VA 19b). In this case, the maximum main tensile stress in the coupling sleeve 3307/7182 x 396 = 0.46 x 396 = 182 MPa

The tensile stress of the coupling sleeve is 325 / 1,1 = 295 (sheet thickness 60 mm, with pipe up to 60 mm wall thickness, the yield strength is 335 MPa). 182/295 <1

Maximum pressure in the contact zone Sleeve / anchor plate:

Decisive is the contact between old anchor plate and the sleeve. Contact area:
B = 15 mm, mean circumference U = 375 mm, A = 37.5 · π · 1.5 = 177 cm ² Tension in the fracture state 7182/177 = 406 MPa Tension in use 3307/177 = 187 MPa

Of the anchor body consists of a CK45N (carbon tempering steel) with a characteristic breaking strength of 660 MPa and a yield strength of 365 MPa (according to test report, see following pages). Thus, the anchor body is not authoritative.

The maximum stress swing width in the prestressing steel is 40.9 MPa (see pages V. A. 249 ff, here page 273a). This is the change in clamping force about 40.9 x 4.05 = 166 kN. The voltage swing width in the sleeve is thus approx. 166/7182 · 396 = 0.023 · 396 = 9 MPa.

These Size is negligible small.

Claims (1)

The coupling sleeve for rehabilitation of a coupling anchor for Litzenspannverfahren with subsequent composite for use in engineering structures such. As bridges, towers, other buildings is characterized by the fact that you subsequently allows a standard-compliant, non-positive structure for connecting two tendons. The claim results from the fact that the two half-shell coupling sleeve body after installation of the standard coupling body and determining the uselessness of the scheduled coupling of the follow-up building section to this, so it can be mounted on him, that the connection of another Koppelankerkörpers is possible and thereby the functioning of a continuous tendon is guaranteed. Furthermore, the invention can be used for a conversion of fixed or Spannankerköpfen in a coupling anchor.