GB2212181A

GB2212181A - Cavity wall tie of rod and binder

Info

Publication number: GB2212181A
Application number: GB8726500A
Authority: GB
Inventors: David Patrick Payne; John Leslie Mayall
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-11-12
Filing date: 1987-11-12
Publication date: 1989-07-19
Anticipated expiration: 2007-11-12
Also published as: GB8726500D0; GB2212181B

Abstract

The invention relates to a method and means for fixing together building components, such as two skins of a cavity wall 10, 11. The components are "tied" together using a rod 13, inserted into holes 17, 18 drilled through the two components, on which are positioned a sleeve 20 such that it spans the cavity between the building components and three washers 22, 24, 26. The sleeve and washers are movable relative to each other and have ports 21, 23, 27 which may be axially aligned to allow passage of a feeder pipe 28 for injecting binder 15 into the holes around the rod, or may be moved into disalignment to effect seals to prevent the binder from escaping from the holes. The sleeve prevents binder from escaping into the cavity and contaminating any insulating layer therebetween and allows for a more efficient fixing. <IMAGE>

Description

METHOD 4 MEANS FOR FIXING BUILDING COMPONENTS TOGETHER This invention relates to a method and means for fixing together building components, particularly for fixing facing panels or skins to outer surfaces of building structures. The invention is particularly applicable to existing structures where the original means of fixing have been found to be defective and in need of being replaced or augmented.

The invention is suitable for traditional building but more especially for the system method of building using pre-formed panels of brick or concrete which are or have been fastened together on site.

Various devices have been proposed for fixing together inner and outer components of the buildings but they tend to be defective for one reason or another because they cannot guarantee an adequate bond to each of the two building components.

Applicants pending application Serial No.

2183687 describeS a method of fixing two building components together by injecting a binding material hole through a system of washers around a rod into a blind bore in a base component and a through hole in a second component to fix the rod in position. The washers seal the holes to retain the binder therein.

This method has a number of disadvantages particularly with the use of low viscosity binding materials which tend to leak out of the bores via air holes in the washers during the injecting and setting processes, defeating the advantages of the system.

Furthermore the positioning of the washers is time consuming and awkward.

The object of the present invention is to overcome these disadvantages.

The present invention provides a method of fixing a first building component to a second building component comprising the steps of forming a blind hole in the second component, inserting a rod into the hole, fixing the rod in the hole and fixing the first building component to the free end of the rod, in which the rod is fixed in the hole by positioning sealing means on the rod, inserting a delivery tube through an orifice in the sealing means such that one end of the delivery tube is adjacent a blind end of the hole and injecting a binder into the hole around an end portion of the rod to fix the rod in the hole.

Preferably the sealing means comprise at least two components being movable relative to each other and comprising either a pair of washers, a washer and a sleeve, or either of the aforesaid combinations plus at least another washer.

The present invention also provides a fixing for use in the above described method comprising a threaded rod and at least a pair of sealing components, each having an internally threaded coaxial bore corresponding to the thread of the rod, each component having an orifice, said components being movable relative to each other to cause said orifices to become axially aligned to allow passage of a delivery tube, or to move the orifices into disalignment to effect a seal.

The present invention further provides a building structure constructed by the above described method comprising a first and second building components and means connecting the components in which the connecting means comprise a rod extending through a hole in said first component and into a blind hole in said second component, a sleeve located on the rod between the first and second building components and penetrating the building components at both ends, and a pair of washers located on the rod spaced from said sleeve sealing the hole in the first component, and binder surrounding the rod in the holes securing it therein.

Further features and advantages of the invention will be apparent from the following description, by way of example, of some preferred embodiments of the invention, the description being read with reference to the accompanying drawings in which:- Figure 1 is a section through part of a building structure showing first and second components secured by a tie in accordance with the present invention; Figure 2 is a view similar to Figure 1 but showing the first stage of the method of fixing the tie; Figure 3 is a view similar to Figures 1 and 2 but showing the second stage of the fixing method; Figure 4 is a perspective view with parts broken away for clarity and showing the same stage as Figure 3; Figure 5 is a view similar to Figure 1 but showing a modification;; Figure 6 is a section view of an inverted roof fixing according to the invention, and Figure 7 is a plan view of a washer used in the fixing of Figure 1.

Referring first to Figure 1, there is shown a building structure comprising outer 10 and inner 11 skins. These skins may be inner and outer skins of a cavity wall of the building or the inner skin 11 may be part of a pre-cast concrete structure or other building structure in which case the outer skin 10 may be a cladding or facing panel for the structure.

For convenience, the outer and inner skin will hereafter be referred to as first and second building components 10, 11.

The building components are secured together by ties 12, one of which is illustrated in Figure 1.

Each tie 12 comprises a stainless steel threaded rod 13 which is secured in a blind hole 17 in the second building component 11 and in a through-hole 18 in the first building component 10. The rod 13 is secured in the blind hole 17 and through-hole 18 by a resin binder 15 which is preferably a thermosetting resin of known type. This may be an epoxy or other suitable resin, preferably having thixotropic properties.

A sleeve 20 is positioned on the rod 13, as shown in Figure 1, said sleeve 20 being of a length at least 20mm and preferably 30mm greater than the distance between building components 10 and 11. The sleeve 20 is internally threaded to correspond with the thread of the rod 13.

Sleeve 20 has a bore 21 extending axially along its length. The purpose of this will be described shortly.

Also positioned on the rod 13 adjacent one end of the sleeve 20 is a washer 22. This is for use when there is to be a two stage fixing process as described below. The washer 22 also has a bore 23 which extends axially through its body. Washer 22 also has an internal thread 32 which corresponds with the thread of the rod 13, see Figure 7.

Spaced on the rod 13 from washer 22 are two further washers 24, 26 which are identical to washer 22, having bores 25, 27 extending axially through their bodies. These washers 24, 26 are positioned adjacent each other.

The sleeve 20 and washers 22, 24, 26 may be formed from any suitable material but are preferably a plastics material such as nylon.

The method of attaching the first and second building components, 10, 11 together will now be described with reference particularly to Figures 2, 3 and 4.

A blind hole 17 is formed in the second building component 11. The hole 17 is drilled with a counterbore 19, which results in a step change in diameter 16. Counterbore 19 has a face 16a. The diameter of the counterbore 19 corresponds to the external diameter of sleeve 20 and has a depth of at least lOmm, but preferably 15mm. The advantage gained in providing a counterbore 19 is that during drilling some of the material 30 of the inner building component 11 will tend to break away, but the counterbore 19 allows the sleeve 20 to pass into the building component 11 and it seats on the face 16a which improves the effective seal between component 11 and sleeve 20 preventing the resin 15 from escaping. The counterbore 19 also facilitates the correct location of the sleeve 20.

A through-hole 18 is drilled in building component 10, with a diameter corresponding to that of counterbore 19, and may either be drilled in position at the same time as counterbore 19 is formed, or at a position remote from component 11.

The rod 13 is inserted into the blind hole 17 after the sleeve 20 and washers 22, 24 and 26 have been screwed into position along the rod 13 with the sleeve and washer bores 21, 23, 25 and 27 axially aligned. The washers 22, 24, 26 and sleeve 20 are in sealing contact with the walls of through-hole 18 when the rod 13 is in position, and the sleeve 20 spans the cavity gap betwen the building components .10 and 11 with an end of the sleeve 20 remote from washer 22 penetrating the counterbore 19 and resting against step 16 and the opposite end of the sleeve 20 penetrating hole 18 to a depth of about 15mm.

A feeder pipe 28 is inserted through the axially aligned. sleeve and washer bores 21, 23, 25 and 27 to the back of blind hole 17 as shown in Figure 2. Resin binder 15 is then introduced into the blind hole 17 from the back and as the hole 17 gradually fills with resin 15 the feeder pipe 28 is gradually withdrawn. The sleeve and washer bores 21, 23, 25 and 27 are of a size and shape such that the feeder pipe 28 can be inserted therein leaving a gap for air to escape from the hole 17, thus ensuring that the hole 17 is effectively filled with resin binder 15.

The feeder pipe 28 is of a section that permits the maximum possible rate of delivery of the resin binder 15 whilst leaving sufficient space within the sleeve and washer bores 21, 23, 25 and 27 to ensure that an air gap is present.

When the blind hole 17 and sleeve bore 21 have been filled with resin 15 the feeder pipe 28 is withdrawn from hole 17 and sleeve bore 21 past washer 22, which is then rotated with respect to the sleeve 20 such that the sleeve bore 21 and washer bore 23 are no longer axially aligned. This provides a seal to prevent the binder resin 15 from escaping from blind hole 17 whilst it sets.

Once the binder 15 has set it provides a secure fixing for the rod 13 in the blind hole 17. It will be appreciated that the binder 15 may permeate into the material of building component 11 to ensure a good fixing for the rod 13.

The second stage of the fixing is shown in Figure 3. Binder resin 15 is injected via feeder pipe 28 into the back of the section of through-hole 18 between washers 22 and 24. As this hole is filled with resin 15 the pipe 28 is gradually withdrawn until the end of the pipe 28 reaches and passes washer 26. At this point the washer 26 is rotated with respect to washer 24 so that the washer bores 25, 27 are no longer aligned, thus sealing the end of the through-hole 18, and providing a neat appearance to the external surface of component 10.

The method described above is illustrated with reference to the fixing of one component to another to form a wall or other vertically extending structure. However, it will be appreciated that the method may equally be used with rod 13 arranged in other orientations, for example diagonal or vertical. Thus, the method may be used to fix a bracket or other fixing to a horizontal concrete slab, as shown in Figure 6.

In this embodiment, two washers 24, 26 are required as used for the outer seal shown in Figure 1. Once the washer 26 has been rotated with respect to washer 24, the resin binder 15 cannot escape from blind hole 17 whilst it sets. Some leakage is to be expected during the injecting process for a vertical or diagional fixing, as a gap must be provided to allow the air in hole 17 to escape.

The outer surface of sleeve 20 and washers 22, 24 and 26 may be grooved or threaded along a whole or part of their length, as shown in Figure 5. The threads or grooves 31 assist in achieving tight seals in the holes 17 and 18 and those on sleeve 20 provide a drip barrier between the components 10 and 11.

The invention is not limited to the embodiments described above and further modifications will be apparent.

The advantages of the device described above include the following. The method, by means of the sleeve 20, ensures that if leakage of the binder occurs, the resin can only escape back within the drill hole and not into the cavity between the first and second components. Furthermore this avoids loss of material and prevents contamination of any material filling the cavity between the components by the resin. This also enables the full length of the embedded rod to be bonded to the walls as there is no loss of material, resulting in a firmer, more reliable fixing. Injecting the resin from the back of the holes 17 and 18 ensures that the holes are completely filled and no gaps retained.

A further modification of the invention lies in the provision of a graduated reservoir to the feeder pipe 28 which allows measured quantities of resin to be injected.

The two step fixing process also allows the possibility of effecting the first part of the fixing, leaving the resin to cure and carrying out pull-off tests before finishing the fixing. When it is deemed unneccesary to adopt the two step fixing process in order to carry out pull-off tests the washer 22 can be dispensed with and the resin injection can proceed as a single process.

Claims

1. A method of fixing a first building component to a second building component comprising the steps of forming a blind hole in the second component, inserting a rod into the hole, fixing the rod in the hole and fixing the first building component to the free end of the rod, in which the rod is fixed in the hole by positioning sealing means on the rod, inserting a delivery tube through an orifice in the sealing means such that one end of the delivery tube is adjacent a blind end of the hole and injecting a binder into the hole around an end portion of the rod to fix the rod in the hole.

2. A method as claimed in claim 1, wherein the sealing means comprise at least two components, each component having an orifice, said components being movable relative to each other to cause said orifices to become axially aligned to allow passage of the delivery tube, or to move the orifices into disalignment to effect a seal.

3. A method as claimed in claim 1 or claim 2 in which one sealing component is a sleeve positioned around the rod and extending between the first and second building components, said first building component having a through hole into which an end of the rod remote from that positioned in the blind hole of the second building component projects.

4. A method as claimed in claim 3 in which the first component is fixed to the rod by withdrawing the binder delivery tube from the sleeve and injecting binder around the rod positioned in the through hole.

5. A method as claimed in claim 3 or claim 4 in which each end of the sleeve projects at least lOmm into the first and second building components.

6. A method as claimed in any one of claims 3, 4 or 5 in which the blind hole in the second building component is counterbored, and one end of said sleeve abuts a face of the counterbore.

7. A method as claimed in any one of the preceding claims wherein the outer surfaces of the sealing means are grooved or threaded along at least a part of their length.

8. A method of fixing a first building component to a second building component substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

9. A fixing for use in the method of claims 1 to 8 comprising a threaded rod and at least a pair of sealing components, each having an internally threaded coaxial bore corresponding to the thread of the rod, each component having an orifice, said components being movable relative to each other to cause said orifices to become axially aligned to allow passage of a delivery tube, or to move the orifices into disalignment to effect a seal.

10. A fixing as claimed in claim 9 in which the sealing components comprise a pair of washers.

11. A fixing as claimed in claim 9 in which the sealing components comprise a washer and a sleeve.

12. A fixing as claimed in claim 10 or claim 11 in which the sealing components further comprise at least another washer.

13. A fixing for use in the method of claims 1 to 7 substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

14. A building structure comprising first and second components joined by the method of claims 1 to 7.

15. A building structure comprising first and second building components and means connecting the components in which the connecting means comprise a rod extending through a hole in said first component and into a blind hole in said second component, a sleeve located on the rod between the first and second building components and penetrating the building components at both ends, and a pair of washers located on the rod spaced from said sleeve sealing the hole in the first component, and binder surrounding the rod in the hole securing it therein.

16. A building structure substantially as hereinbefore described with reference to and as shown in the accompanying drawings.