GB2254631A

GB2254631A - Underpinning

Info

Publication number: GB2254631A
Application number: GB9104628A
Authority: GB
Inventors: John Francis Mullarkey
Original assignee: GUARDIAN FOUNDATIONS PLC
Current assignee: GUARDIAN FOUNDATIONS PLC
Priority date: 1991-03-05
Filing date: 1991-03-05
Publication date: 1992-10-14
Also published as: GB9104628D0

Abstract

A method of underpinning a building involves the provision of a trench alongside the walls of the building so as to expose the footings (F), and one or two courses of brickwork are removed to provide a channel (C) extending around the walls, load bearing members (20) being utilised to support the walls temporarily. Short extension trenches (E) are then dug outwardly from the trench at spaced intervals, and from these extension trenches holes (H) are augered, bored or driven in a generally vertical direction. A reinforcing cage (R1) is located in the channel as to extend around the building, and this is intermeshed with a secondary reinforcing cage located in each of the extension trenches (E). Additional reinforcing rods (R3) are located in the augered holes so as to interleave with the reinforcing cages. A suitable casting material such as a cementitious mix is then poured into the trench, so as to flow into the channel (C) and into the holes (H), to provide a support for the building. <IMAGE>

Description

Title: "Improvements relating to underpinning" Description of the Invention This invention is concerned with improvements relating to underpinning. The invention has been devised for the underpinning of walls of domestic premises, in which context the invention will hereinafter be described. It is however to be appreciated that the invention is applicable to underpinning in general, and specifically to the underpinning of walls other than those of domestic premises.

According to this invention there is provided a method of underpinning a wall comprising: [a] Providing an elongate channel in or beneath the wall; [b] Providing a plurality of elongate holes extending alongside the wall generally downwardly; [c] Locating reinforcing means in the channel and in the holes, said reinforcing means including elements extending from each hole into the channel; [d] Casting a suitable material into the holes and channel to provide a supporting element extending generally horizontally in part at least into the wall, downwardly-extending support members and cantilever portions extending from the support members to the supporting element, the supporting element, the support members and the cantilever portions being integral.

Preferably the channel is provided at a level below the ground level, preferably above footings of the wall. If desired the channel may extend only part-way into the wall, e.g. one course, but may extend completely through the wall, conveniently load bearing members being utilised to support the wall above the channel whilst the method is being completed.

Conveniently the holes are provided by augering, boring or driving operations.

Where the method is used to underpin a building, preferably the support element extends as a one-piece ring around the building, the support members being provided at spaced intervals along each of the sides of the building, although if desired the support element may extend along one wall or part of one wall, or (if desired) a discontinuous ring may be utilised.

There will now be given a detailed description, to be read with reference to the accompanying drawings, of a preferred embodiment which has been selected for the purposes of illustrating the invention by way of example.

In the accompanying drawings: FIGURE 1 is a perspective view illustrating a stage in the performance of the invention; FIGURE 2 is a vertical sectional view showing the relationship of vertical support members with the horizontally-extending supporting element; and FIGURE 3 is a plan view taken on Figure 1.

The preferred embodiment of the invention is a method of underpinning a domestic premises, where a large section of the building, if not the building in its entirety, needs underpinning support.

It is preferred that a trench T is dug around the walls of the building B so as to expose the footings F of the building, - and one or two courses of brick- work are removed to provide a channel C extending around the walls, load bearing members 20 being utilised to support the walls onto the footings F temporarily.

Short extension trenches E are then dug outwardly from the trench T at spaced intervals around the building, and from these extension trenches holes H are augered, bored or driven in a generally vertical direction.

A reinforcing cage R1 is located in the channel C so as to extend around the building, and this is intermeshed with a secondary reinforcing cage located in each of the extension trenches E, as shown in Figure 1.

Additional reinforcing rods R3 are then located in the augered holes, so as to interleave with the reinforcing cages R1 and R2. A suitable casting material such as a cementitious mix is then poured into the trench T, so as to flow into the channel C, into the holes H, to provide a continuous reinforced ring within the channel C, which is supported by the support elements S located with the holes H, through the intermediary of a cantilever portion P [see Figure 2]. In this manner a firm support is provided for the building which may if desired extend around the entire periphery of the building, although of course the invention may be utilised to provide for such support along part only of the building.

As shown in Figure 2, corrugated material G may be utilised between the cantilever portion P and the pre-existing foundation as an "anti-heave" precaution.

The features disclosed in the foregoing description, or the accompanying drawings, expressed in their specific forms or in the terms or means for performing the desired function, or a method or process for attaining the disclosed result, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

ClAIMS:

1. A method of underpinning a wall comprising: [a] Providing an elongate channel in or beneath the wall; [b] Providing a plurality of elongate holes extending alongside the wall generally downwardly; [c] Locating reinforcing means in the channel and in the holes, said reinforcing means including elements extending from each hole into the channel; [d] Casting a suitable material into the holes and channel to provide a supporting element extending generally horizontally in part at least into the wall, downwardly-extending support members and cantilever portions extending from the support members to the supporting element, the supporting element, the support members and the cantilever portions being integral.

2. A method according to Claim 1 wherein the channel is at a level below ground level.

3. A method according to Claims I and 2 wherein the channel is above footings of the wall.

4. A method according to any one of the preceding claims wherein the channel extends only part-way into the wall.

5. A method according to any one of Claims 1, 2 and 3 wherein the channel extends completely through the wall.

6. A method according to one of Claims 4 and 5 involving the use of load bearing members to support the wall above the channel whilst the method is being completed.

7. A method according to any one of the preceding claims wherein the holes are provided by augering, boring or driving operations.

8. A method according to any one of the preceding claims wherein the channel extends along one side only of the building, or part only of one side.

9. A method according to any one of Claims 1 to 7 wherein the channel extends around the building to provide a continuous or discontinuous ring.

10. A method according to any one of the preceding claims involving the use of corrugated material between the cantilever portion and the existing foundation, as an "anti-heave".

11. A method of underpinning a wall, when carried out substantially as hereinbefore described with reference to the accompanying drawings.

12. Any novel feature or novel combination of features as hereinbefore described and/or as shown in the accompanying drawings.