GB2109437A

GB2109437A - A structural member having a stressing element and a reinforcing element

Info

Publication number: GB2109437A
Application number: GB08232758A
Authority: GB
Inventors: Max Birkenmaier
Original assignee: Bureau BBR Ltd
Current assignee: Bureau BBR Ltd
Priority date: 1981-11-17
Filing date: 1982-11-17
Publication date: 1983-06-02
Also published as: NL8204442A; SE8206508L; GB2109437B; DE3242396A1; CH653729A5; SE8206508D0

Abstract

The reinforcing element 4 is given the shape of a tube and the stressing element 5 is located within this tube. The stressing element 5 is a stranded wire of which one end is held in an end anchor 6 by means of wedges 8. The other end of the stressing element 5 is mounted in a recessed sleeve 17 intended to receive further wedges 18. The stressing element 5 is thus positively protected against environmental influences and mechanical damage. The structural member can be a foundation anchor comprising mortar 7 injected into a borehole 2 in soil 3 and passing through a concrete wall 10. <IMAGE>

Description

SPECIFICATION A structural member having a stressing element and a reinforcing element This invention relates to a structural member having a stressing element and a reinforcing element.

The application of a structural member, in which the stressing element and the reinforcing element are arranged side by side is commonly known. However, such commonly known structural members incorporate a number of drawbacks. A first drawback is the necessity of taking individually measures of laying the stressing element of the reinforcing bar within a structure, which is often-times time-consuming and, furthermore, costly. It is, furthermore, generally known that the stressing element must be painstakingly protected against specifically a corrosion thereof. This leads to a further considerable expenditure.

It is therefore an object of the invention to provide a structural member of the kind mentioned above, which can be laid or applied, respectively, in a preassembled manner and in which the stressing element is positively protected against corrosion.

According to the invention there is provided a structural member, in which the reinforcing element is shaped as a tube and the stressing element is located within said tube.

In the accompanying drawings: Fig. 1 is a view of a longitudinal section of the structural member; and Fig. 2 is a view of a longitudinal section of a junction of two structural members of figure 1.

In fig. 1 an embodiment of the structural member in the form of a foundation anchor is shown, of which one end is mounted in the inner space of a bore-hole 2 and the other end of which is supported at a building structure 3. The structural member has a tube-shaped reinforcing element 4, which tube is provided with ribs located at the outer surface thereof. These ribs are arranged such that they define an outer thread. A stressing element 5 is located within the tube 4, which is in this embodiment a stranded wire. This stressing element may however also be one solid wire. The inner diameter of the tube 4 is larger than the outer diameter of the stressing element 5 such that an intervening space is provided between the reinforcing element 4 and the stressing element 5.This allows an application of a corrosion protection agent on the surface of the stressing element 5, which agent may now be applied in a satisfactory thick layer. Accordingly, a first measure is taken against a corroding of the stressing element. In addition to the above the stressing element treated as mentioned is surrounded by the tube-shaped reinforcing element 4, which does not only protect the stressing element 5 against detrimental influences of the environment but also protects the stressing element 5 against mechanical injury.

The end of the anchor which is located within the bore-hole 2 comprises an end anchor, which is kept in place by means of injected mortar 7. The end anchor comprises a recessed sleeve 6 for receiving wedges and a set of wedges 8 is located therein. The individual wedges of this set of wedges 8 clamp the stressing element, the stranded wire between each other. This side of the end anchor comprising the sets of wedges 8 is provided with a cap 9, which protects the individual members of the end anchor against environmental influences, and specifically against corrosion. At the other side thereof the tubeshaped reinforcing element 4 abuts tightly the recessed sleeve 6 such that also at this side no water can penetrate into the inner space of the end anchor.

The soil 3 is provided with a concrete wall 10, against which the other end of the anchor is supported. An undulated tube 11 is located within the hole in the concrete wall 10, which is aligned with the bore-hole 2, which undulated tube 11 extends through the concrete wall 1 0. At the end area of the undulated tube 11 a recess 1 2 is shaped in the concrete wall 10. An anchor plate 13 is located at the bottom surface of this recess 12, which anchor plate 1 3 distributes the stress exerted by the anchor onto a larger surface area of the concrete wall 1 0. The anchor plate 1 3 comprises a threaded opening into which the reinforcing element 4, which has the shape of a tube with an outer thread, is threaded.

A nut 1 5 is screwed onto the end of the tube 4 which projects out of the anchor plate 1 3. This end of the anchor is provided further with a tensioning device, allowing a stressing of the stressing element 5.

The tensioning device comprises a ring 16, which surrounds the nut 1 5 screwed onto tube 4 and the height of ring 1 6 exceeds the height of nut 1 5. At one end this ring 1 6 abuts the anchor plate 13 and at the other end a second recessed sleeve 1 7 for Che receipt of wedges is in contact with said ring 1 6. The outer contour of the recessed sleeve 17 is circular and a second set of wedges 1 8 is pressed into this recessed sleeve 1 7.

When installing the structural member its stressing element 5 will initially be coated by an insulating grease and thereafter the anchor is assembled outside of the bore-hole 2. Thereafter this anchor will be inserted into the bore-hole 2, followed by a filling of the bore-hole by means of injected mortar 7. After the mortar 7 has set and accordingly the end anchor 6 is held rigidly within the bore-hole 2, the stressing element 5 can be stressed or tensioned, respectively, and thereafter arrested in the stressed condition by means of the wedges 1 8.

If long bore-holes are present there may be a problem due to an insufficient length of the reinforcing tubes 4. In such case utilisation is made of the ribs of the reinforcing tubes 4, which, as mentioned earlier, define a thread. To this end a threaded sleeve 20 (fig. 2) is used for coupling two individual reinforcing tubes 4, which threaded sleeve 20 bridges the junction 21 of the reinforcing tubes 4.

Claims

1. A structural member having a stressing element and a reinforcing element, characterised in that the reinforcing element is shaped as a tube and in that the stressing element is located within said tube.

2. A structural member according to claim 1, wherein the reinforcing tube has a profiled outer surface.

3. A structural member according to claim 2, wherein the reinforcing tube comprises an outer thread.

4. A structural member according to claim 3, wherein there is provided a nut which is intended to bridge the junction of two reinforcing tubes having an outer thread.

5. A structural member according to claim 1, wherein the stressing element is a solid wire or a stranded wire.

6. A structural member substantially as herein described with reference to the accompanying drawings.