GB2581379A

GB2581379A - Prop for supporting a wall

Info

Publication number: GB2581379A
Application number: GB1902097.3A
Authority: GB
Inventors: C Sgueglia David; A Hicks Robert
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-02-15
Filing date: 2019-02-15
Publication date: 2020-08-19
Anticipated expiration: 2039-02-15
Also published as: GB2581379B; GB201902097D0

Abstract

A wall prop 200 and method for supporting a wall 205. The wall prop 200 comprises a first support member 220 extending in a first direction for entering and supporting a wall 205, and a second support member 225, spaced from and substantially parallel to the first direction. The first and second support members are rigidly connected, such that the second support member 225 opposes, in use, a turning moment imparted on the first support member 220 by the wall 205. A later embodiment relates to a method of supporting a wall 205 using said prop. The method comprises the steps of inserting a first support member 220 of the wall prop into a first hole 237 at least part way in the wall 205, supporting the prop 200, removing at least a lower portion of the wall beneath the first hole 237, wherein the supporting is such that a second support member 225 of the wall prop 200 opposes a turning moment imparted on the first support member 220 by the wall 205.

Description

PROP FOR SUPPORTING A WALL

Field of the Invention

[0001] The invention relates to building equipment, especially devices for supporting a wall during building work.

Background

[0002] During building work, especially refurbishment work of an existing building, it is often required to support an upper section of a wall while working on a lower section of the wall. The lower section of the wall may be being removed to make way for an extension or to add patio doors. Alternatively, the foundations of the wall may need to be strengthened or refurbished, during which the wall above requires support.

[0003] Needling is a method for the support of a wall during building work. Needling refers to the process of inserting a temporary beam through a wall for wall prop of the wall above the level of the temporary beam. Effectively, the temporary beam is supporting a wall that is already built. Needling can support a long stretch of wall by using a series of needles at defined intervals. When a series of needle beams are in place, old wall and/or old foundation can be removed and excavation performed to the level of the bearing of the new foundation can begin.

[0004] Fig. 1 shows a prior art setup 100 of needling. A pre-existing wall 105 is comprises an inner skin 106 and an outer skin 107 with a gap for insulation therebetween, also referred to as a cavity wall. A floor joist 110 is supported by the inner skin 106 of the wall 105. An opening/hole 111 has been created in a section of the wall 105. The opening/hole 111 is made in the outer skin 107 and the inner skin 106 such that a needle 115 can be passed through the section of the wall 105. Needle 115 is a steel beam. The needle is supported by a first prop 120 on a first side of the wall 105 and a second prop 125 on a second side of the wall. The first prop 120 on the first side of the wall is be inside a building and may extend from the floor of the building to the level of the needle.

Alternatively, and as shown in Fig. 1, the first prop supports the floor joist 110, and a third prop 130 is required between the floor joist 110 and needle 115 to support the needle. A fourth prop 135 is also used to support the floor joist.

[0005] The needle 115 is not fixed to the props 125 and 130, but merely rests upon them. Props 125 and 130 are adapted to resist forces in the direction of their length (longitudinal forces). The wall 105 is supported by the centre of the needle 115 (in the length-wise direction of the needle 115) in order to distribute the weight of the upper section 108 of the wall 105 evenly between the props 125 and 120/130.

[0006] It will be understood that to support a length of wall, a plurality of needles will be required at intervals determined by structural calculations to ensure that the upper section 108 of the wall 105 is adequately supported. A prop 135 will be required to support each floor joist 110.

[0007] With the floor joist 110 and the upper section 108 of the wall 105 supported by the needle 115, the lower section 109 of the wall 105 is be removed. Foundations for the wall 105 may then be renovated before the lower section 109 of the wall 105 is rebuilt. If the lower section 109 of the wall 105 is removed in order to add patio doors or to facilitate an extension, then a beam 141 is inserted to support the floor joist 110 and upper section 108 of the wall 105. The beam 141 is supported by the existing wall 105 (or a strengthened version thereof) at its ends.

[0008] Needling is usually used in building renovations or extensions. There will be fixtures and fittings present within the building. There may even be people living in the building during such work. Needling, as shown in Fig. 1, can result is a hidden bulkhead. A hidden bulkhead is where the beam 141 is concealed in the ceiling. As a result there is no unsightly bulkhead viewable in a lower room, and casting shadows therein. A visible bulkhead is necessary if the needle 115 penetrates the wall 105 below the level of the floor joist 110.

[0009] Needling to provide a hidden bulkhead is invasive. The needle 115 must penetrate the wall 105 above the level of the floor joist 110, i.e. at first floor level. This causes significant interference in the room above the floor joist. For example, it frequently results in the removal of bathroom fixtures (tiling, baths, toilets, and other plumbing) or electrical cables. This is not only intrusive to the occupants of the building, but can render the building uninhabitable during the building work. As a result, it increases costs by necessitating the refurbishment of the room above the floor joist 110.

[00010] Fig. 1B shows a second prior art setup for propping a wall 155. The device shown in Fig. 1B is commonly known as a Strong BoyTM. The wall 155 is a single skin wall consisting of bricks held together by mortar 156. To fit device 150, a section of mortar 156 is chiselled out from between two courses of brick to produce a slit. The device 150 comprises a blade 160 made from a thin metal plate for insertion between courses of bricks. The blade 160 is inserted and hammered into the slit. A prop 165 is inserted into the free end of the device 150 to support the device 150 and wall 155.

[00011] Because the blade 160 of device 150 must be thin enough to fit between courses of bricks, the strength of the blade is limited. As a result the span of blade 160 is limited and the prop 165 must be positioned close to the wall 155, limiting space to work on the wall. The weight of wall to be supported is also limited. While the device 150 may be used on walls having two bricks placed side-to-side the mortar between courses in each of the two skins must coincide. The above reasons also mean that the device cannot be used on walls having cavities.

[00012] It is an object of this invention to provide an improved wall prop for supporting a wall which, when used to facilitate the removal of a lower section of the wall, reduces invasiveness, time and costs associated with supporting the wall. The wall prop can be used to provide a hidden bulkhead finish.

Summary of the Invention

[00013] The invention relates to a wall prop for supporting a wall. According to an aspect, the wall prop comprises a first support member extending in a first direction for entering and supporting a wall; and a second support member, spaced from and substantially parallel to the first direction. As a result of the invention, the wall prop need only be used from one side of a wall, significantly reducing the invasiveness of the propping process. The wall prop is preferably a single-sided needle prop. In use the first support member of the prop can support the weight of the upper part of the wall, enabling a wall section beneath the first support member to be removed. In other words, the prop allows for work on an existing wall or foundations and can facilitate insertion of a hidden beam for a bulkhead-free finish.

[00014] Preferably the prop is configured such that the second support member opposes, in use, a turning moment imparted on the first support member by the wall. In an example, the first and second support members are rigidly connected, to achieve this.

[00015] According to a further aspect, the wall prop further comprises a third support member, wherein the first and second support members are rigidly connected to the third support member, and wherein the third support member is substantially perpendicular to the first and second support members. The third support member spaces the first and second support members, providing a convenient area in which to work. The rigid connections ensure that the prop flexes to a limited degree and therefore a supported wall does not move.

[00016] According to a further aspect, the first support member is connected to the third support member towards a first end of the first support member and towards a first end of the third support member; and the second support member is connected to the third support member towards a first end of the second support member and towards a second end of the third support member.

[00017] According to a further aspect, there is provided additional means for acting on the second support member to assist in opposing the turning moment imparted on the first support member by the wall, for example, a prop for supporting the second support member and/or a prop for the third support member, which can be known props. In an alternative embodiment, the wall prop (for example, the second support member) is supported by the wall itself (for example, a lower portion of the wall).

[00018] According to a further aspect, the wall prop is manufactured from reinforced hollow section (RHS) steel. RHS steel has a rectangular or square cross-section with rounded corners. In use, the rounded corners increase the contact area between the prop and the wall, decreasing the applied pressure. RHS steel is strong in both flexural directions, thus reducing the chance of damage due to rough handling. In turn, this improves the reliability of the prop.

[00019] According to a further aspect, the second support member is longer than the first support member. This enables an end of the second support member to fully penetrate a lower section of wall, and reduces the force required at an end of the second support member to oppose a turning moment imparted by the wall on the first support member. In use, it improves stability of the prop and the propped structure, and enables the second support member to be supported by an additional prop.

[00020] The invention further relates to a method of supporting a wall using a wall prop, the method comprising: inserting a first support member of the wall prop into a first hole at least part way in the wall; supporting the prop; removing at least a lower portion of the wall beneath the first hole; and wherein the supporting is such that a second support member of the wall prop opposes a turning moment imparted on the first support member by the wall. As a result, the wall prop need only be used from one side of a wall, preferably the outside, significantly reducing the invasiveness of the propping process.

[00021] According to an aspect, the first hole/first support member does not fully penetrate the wall. This reduces invasiveness, cost, and the time taken for the propping process because contents of a room on the second side of the wall are not interfered with.

[00022] According to a further aspect, the first support member is inserted from a first side of the wall, and the method further comprises: inserting the second member into a second hole at least part way in the wall, wherein the second hole is vertically spaced from the first hole.

[00023] According to a further aspect, an end of the second support member passes through the second hole to the second side of the wall, and the method further comprises: positioning a prop on the second side of the wall, to support the second support member to oppose the turning moment imparted on the first support member by the wall. The wall prop is adapted to be supported by standard props. This enables an end of the second support member to fully penetrate a lower section of wall, and reduces the force required at an end of the second support member to oppose a turning moment imparted by the wall on the first support member. Supporting the second support member on the second side of the wall improves stability of the prop and the propped structure.

[00024] According to a further aspect, the second support member is supported by the wall to oppose the turning moment imparted on the first support member by the wall. In this aspect, no prop is needed to support the second support member, reducing complexity.

[00025] According to a further aspect, the method further comprises: positioning a prop on the first side of the wall to support the wall prop.

[00026] According to a further aspect, the method further comprises using a wall prop as described herein.

[00027] According to a further aspect, the method further comprises positioning the third support member to be substantially parallel to the wall. This can improve the effectiveness of the prop.

[00028] According to another aspect, the invention provides a method of propping a wall comprising inserting a first support member to support the wall from one side of the wall, preferably the outside, and providing means for acting on the first support member to oppose the turning moment imparted on the prop by the wall, wherein the acting means is also on the same side of the wall. For example, the acting means could be a counterweight or an anchor driven into the ground.

[00029] A preferred embodiment or embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings.

Brief description of the drawings

[00030] Fig. 1A is a cross-sectional schematic of a prior art setup for propping a wall.

[00031] Fig. 1B is a second cross-sectional schematic of a prior art setup for propping a wall.

[00032] Fig. 2 is an example wall prop, shown supporting a wall.

[00033] Figs. 3A and 3B show a first and second example cross section for the frame portion and a hole in a wall to be supported.

[00034] Fig. 4 shows an example wall prop, shown supporting a wall.

[00035] Fig. 5 is a third example wall prop having an extended third support member.

[00036] Fig. 6 is a fourth example wall prop having a pivotable leg at the second end of the second support member Fig. 7 is a fifth example wall prop wherein the second support member is connected to the third support member towards the second end of the third support member [00037] Fig. 8 is a sixth example wall prop having strengthening members at the rigid connections.

[00038] Fig. 9 is a seventh example wall prop having a diagonal strengthening member.

[00039] Fig. 10 is an eighth example wall prop having a counterweight to balance a moment imparted by the wall on the wall prop.

Detailed description

[00040] The following description includes specific details for the purpose of providing an understanding of various concepts, but it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. The following description is not intended to represent the only configurations in which the concepts described herein may be practiced.

Wall prop [00041] Fig. 2 shows a wall prop 200 and a wall 205. Wall prop 200 has a third support member 215 which is configured to be substantially parallel to the wall 205 to be supported. The third support member 215 has a first end 216 and a second end 217. The first end 216 of the third support member is shown to be the upper end in Fig. 2.

[00042] Wall prop 200 has a first support member 220. The first support member has a first end 221 and a second end 222. The first end 221 of the first support member 220 is rigidly connected to the third support member 215. The rigid connection of the first support member 220 to the third support member 215 is toward the first end 216 of the third support member 215. The rigid connection of the third support member 215 to the first support member 220 is toward at the first end 216 of the third support member 215. The first support member 220 is approximately perpendicular to the third support member 215.

[00043] Wall prop 200 has a second support member 225. The second support member has a first end 226 and a second end 227. The first end 226 of the second support member 225 is rigidly connected to the third support member 215. The second support member 225 is rigidly connected to the third support members 215 between the first end 216 and the second end 217 of the third support member 215. The distance between the rigid connections for the first support member 220 to the third support member 215 and the second support member 225 to the third support member 215 is a minimum of 700 mm. This provides sufficient distance between the first support member 220 and the second support member 225 to work on the lower section of the wall, for example to prepare the wall for -and to install -beam 241. The distance between the first support member 220 and the second support member 225 may be 700 to 2000 mm, or more preferably 1400 to 1600 mm. In an example, said distance may be 1550 mm. The second support member 225 is approximately perpendicular to the third support member 215.

[00044] Together, the third support member 215, first support member 220, and second support member 225 form a rigid frame. A rigid frame in structural engineering is the load-resisting skeleton constructed with straight or curved members interconnected by mostly rigid connections which resist movements induced at the joints of members. Its members can take bending moment, shear, and axial loads.

[00045] As shown in Fig. 2, the rigid connection of the second support member 225 to the third support member 215 is toward the second end 217 of the third support member 215. The distance between the rigid connection of the second support member 225 to the third support member 215 and the second end 217 of the third support member 215 is around 450 mm. In an example the distance is between 100 and 600 mm, or preferably.

[00046] In this example, the second end 217 of the third support member 215 is arranged to be supported by a first prop 230. A baseplate 218 is provided at the second end 217 of the third support member 215 to spread the load over a corresponding baseplate on the first prop 230. The second end 217 of the third support member attaches to the prop 230. Fixings are present in the baseplate 218 to attach the baseplate to the prop 230. The fixings are holes to enable the baseplate 218 to be bolted to the first prop 230. The first prop 230 is length adjustable and sufficiently strong to support the wall prop 200 and the wall to be supported. Such props are known to those in the art, for example an Acrow PropTM.

[00047] In this example, the second end 227 of the second support member 225 is arranged to be supported by a second prop 240. The second prop 240 is length adjustable and sufficiently strong to support the wall prop 200 and the wall to be supported. Such props are known to those in the art, for example an Acrow PropTM A baseplate 228 is provided proximal to the second end 227 of the second support member 225 to spread the load over a corresponding baseplate on the second prop 240. The second end 217 of the second support member is in contact with and supported by to the second prop 240. Fixings are present in the baseplate 228 to attach the baseplate to the second prop 245. The fixings are holes to enable the baseplate 228 to be bolted to the second prop 245.

[00048] First prop 230 and second prop 240 are also referred to as "legs".

[00049] The support at the second end 227 of the second support member 225 enables the wall prop 200 to resist a moment, or turning force imparted on the wall prop 200 by a wall 105 to be supported. Without the support at the second end 227 of second support member 225, the wall prop 200 would be prone to topple due to the weight of the wall 105.

[00050] Fig. 2 shows the second support member 225 to be longer than the first support member 220. In an example, the second support member 225 is 150 mm longer than the first support member. In an example, the first support member has a length of 400 to 1000 mm, or more preferably 600 to 800 mm. In an example, the first support member has a length of 670 mm. The second support member 225 has a length of 550 to 1300 mm, or more preferably 750 to 950 mm. In an example, the second support member 225 has a length of 820 mm.

Wall prop in use [00051] The wall prop 200 is shown in use in Fig. 2. Fig. 2 shows a double-skinned wall (cavity wall) 205 having an inner course of blocks 206 (also referred to as inner skin or inner wall), and an outer course of bricks 207 (also referred to as outer skin or outer wall). A gap for insulation is shown between the inner skin 206 and outer skin 207. The double-skinned wall 205 is merely an example, and the wall prop is suitable for use with single-skinned walls, walls having more than two skins and walls where each of one or more skins is a double course of blocks.

[00052] A prop 235 is provided to support a floor joist 210. A bath 211 is shown in a room in the upper floor (e.g. a first floor of a house). As can be seen, the bath 211 has not been removed in order to install wall prop 200.

[00053] Wall 205 is shown having an upper section 208 and a lower section 209.

Wall prop 200 is supporting the upper section 208 of wall 205. A section of the first support member 220 is in contact with and supporting the upper section 208 of the wall 205. The section of the first support member 220 in contact with and supporting the wall 205 is towards the second end 222 of the first support member 220.

[00054] In order to support the upper section 208 of the wall 205, an opening, for example a hole, is drilled in the wall 205 at a location above which the wall 205 is to be supported by the wall prop 200. This hole will be referred to as upper hole 237. The upper hole 237 can be drilled from an external side of the wall 205. The hole is first drilled using a large bore core drill (which does not evacuate the matter within the diameter of the drill), followed by a number of smaller holes within the diameter of the core drill in order to break the cored section from the wall. This enables a smooth-sided large bore hole to be made in the wall, without damaging the wall. In an example, the large bore core drill has a diameter of 110 mm and three smaller holes, each of 50 mm diameter are drilled within the 110 mm core.

[00055] The upper hole 237 is drilled only part way through the inner skin 206 of the wall 205. The proportion of the thickness of inner skin that needs to be drilled depends upon the weight of the upper section 208 of the wall 205 and the properties of the inner skin 206 of the wall 205. In an example, the hole is drilled 50-70 mm into the inner skin 206 of the wall 205, this is around 50-70% of the distance through a standard breeze block (a standard breeze block having dimensions of 440x215x100mm).

[00056] In the case of a double skinned wall, the hole 237 is drilled fully through the outer skin 207 of the wall 205. The hole is sized to accommodate the second end 222 of the first support member 220. Because the hole need not be drilled fully through the inner skin 206 of the wall 205, fixtures (such as bath 211), fittings, and living space need not be unduly interfered with.

[00057] In this example, a second hole 236 (also referred to as the lower hole 236) is drilled in the lower section 209 of the wall 205. The second hole 236 is located and sized appropriately to allow the second end 227 of the second support member 225 to pass through the wall 205.

[00058] The wall prop 200 is positioned with the third support member 215 substantially parallel to the wall 205. The second end 222 of the first support member 220 is inserted into the upper hole 237 in the wall, meanwhile the second end 227 of the second support member 225 passes through the second hole 236 in the wall 205. In this example, the second support member 225 fully penetrates the wall 205, such that the second end 227 of the second support member 225 is to the inside of the inner skin 206 of the wall 205.

[00059] The wall prop 200 is supported at the second end 217 of the third support member 215 and at the second end 227 of the second support member by props 230 and 240, respectively. The third support member 215 and props 230 and 240 are substantially parallel to the wall 205. Thus, the first support member 220 and the second support member 225 are substantially perpendicular to the wall 205.

[00060] Once positioned, the wall prop 200 supports the weight of the upper section 208 of the wall 205. The lower section 209 of the wall 205 can be removed. The lower section can be repaired and rebuilt if necessary. In many cases, the lower section 209 of the wall 205 is removed to create a new opening in the wall 205. In this case, the lower section 209 of the wall 205 is not rebuilt, instead a beam 241 is fitted to take the weight of the floor joist 210 and upper section 208 of wall 205. The beam 241 is suitably supported at its ends, for example by the existing wall or a strengthened wall. The beam 241 is shown as an I-beam, but could be any other suitable beam known to those in the art.

[00061] The length of the first support member 220 allows the third support member 215 to be spaced from the wall 205. This has an advantage of enabling work to be carried out on the wall 205 (for example, its demolition) and giving space for the positioning and installation of the beam 241.

[00062] The wall prop 200 supports the inner and outer skins of the wall concurrently. This allows the beam 241 to be installed to support the joist 210 in such a manner that the beam 241 is not visible (does not protrude beneath the level of a ceiling) once building work is complete, i.e., the bulkhead is not visible.

[00063] In use, once the lower section 209 of the wall 205 is disturbed or removed, the weight of the upper portion 208 of wall 205 imparts a downward force on the second end 222 of the first support member 220. Because the second end 222 of the first support member 220 is spaced from the third support member 215 (by the length of the first support member 220), the force towards the second end 222 of the first support member 220 imparts a turning moment on the wall prop 200. This turning moment is in the anticlockwise direction when viewed in Fig. 2. In other words, the product of the force and its distance from a pivot is a measure of its turning effect, and is called the moment of the force.

[00064] The rigid connections between the first support member 220 and the third support member 215 and between the third support member 215 and the second support member 225 act to transmit the turning moment throughout the wall prop 200.

[00065] The support 240, in collaboration with the second support member 225, towards the second end 227 of the second support member 225 is configured to negate the turning moment imparted on the wall prop 200 by the upper section 208 of the wall 205. In the example of Fig. 2, a prop 240 is used to support the second end 227 of the second support member 225 to allow the wall prop to negate the turning moment. It can be considered that the support towards the second end 227 of the second support member 225 provides a turning moment in the clockwise direction which negates the anticlockwise turning moment imparted by the wall 205 towards the second end 222 of the first support member 220.

[00066] For balance, the sum of the 'clockwise' moments is the same as the sum of the 'anticlockwise' moments. In this example, the second support member 225 is longer than the first support member 220. This means that the large force of the weight of the upper section 208 of wall 205 on one side of a fulcrum (towards the second end 222 of the first support member 220) can be balanced by smaller forces on the other (towards the second end 227 of the second support member 225), because the smaller force is further from the fulcrum. However, generally, the second support member 225 can be the same length as the third support member 220 and still adequately perform the supporting function of the wall 205.

Other features of the wall prop [00067] It will be appreciated that multiple wall props 200 may be needed to support a given wall 205 depending upon the span of the wall 205 to be supported and the weight of the upper section 208 of the wall 205. The wall props 200 may be restrained laterally (to one another and/or to other objects) during use. The wall props can be provided with fixings for this purpose. In an example each wall prop 200 is arranged to support a weight of 200 to 800 kg, preferably 300 to 400 kg of wall 205 positioned toward the second end 222 of the first support member 220.

[00068] The third support member 215, first support member 220, and second support member 225 of the wall prop 200 are preferably formed from reinforced hollow section (RHS) steel. RHS steel has a square or rectangular profile with rounded corners, the rounded corners are a product of the process for manufacturing RHS steel. Unlike an I-beam, a H-beam or a channel-beam, a RHS beam is equally resistant to all directions of flexural bending. Thus, a wall prop 200 formed from RHS beams is more resistant to bending as a result of handling than if the wall prop 200 were made from beams of other cross section.

[00069] A cross section 305 of a square RHS steel beam is shown in Fig. 3A. A circle 310 is shown representing the hole drilled in the wall 205, and the section of the RHS steel beam can be considered to be the second end 222 of the first support member 220.

It can be seen that the rounded corners of the RHS beam act to distribute the weight of the wall 205 over a larger area of the beam and the hole. This reduces the chance of damage to beam and hole, and improves reliability. The RHS section used in Fig. 2 has have dimensions of 90x50x5mm. The skilled person will understand that other dimensions of RHS beam may be used depending on the required strength of the wall prop.

[00070] The skilled person will understand that other sections of beam (for example, I-beam, H-beam, channel-section beams, or circular-section beams) could be used. An example of an I-beam is shown in Fig. 3B. The beam 315 is shown in cross section in hole 320.

[00071] In this case (and in the case of any beam), the second end 222 of the first support member 220 is provided with an arc section 321 to distribute the weight of the wall over a greater area of the second end 222 of the first support member 220 and the hole 320.

[00072] Fig. 4 shows a second example of a wall prop 400. Wall prop 400 is configured and used as described for wall prop 200. Like reference signs in Fig. 4 have like identity and function to like reference signs in Fig. 2.

[00073] In Fig. 4, the second support member 425 is the same length as the first support member 220. In this case the second end 427 of the second support member 425 is configured to be supported by (and is shown being supported by) a lower portion 445 of a lower section 409 of the wall 205. Wall prop 400 is be used to remove the upper portion 446 of the lower section 409 of the wall 205. This enables the addition of a new window in the upper portion 446 of the lower section 409 of the wall 205, or the replacement of a lintel or beam above an existing window opening. In Fig. 4, the hole 236 in the wall 205 for the second support member 425 is shown as fully penetrating the wall 205, however, and to reduce intrusion, this need not be the case. The depth of this hole is determined in a similar manner to that described above for the second end 222 of the first support member 220. Furthermore, the second end 427 of the second support member 425 does not protrude fully through the inner skin 206 of the wall 205.

[00074] Fig. 5 shows a third example of a wall prop 500. Wall prop 500 is configured and used as described for wall prop 200. Like reference signs in Fig. 5 have like identity and function to like reference signs in Fig. 2.

[00075] In the example shown in Fig. 5, the second support member 225 is rigidly connected to the third support member 515 approximately halfway between the first end 516 and the second end 517 of the third support member 515. The position of the second support member 225 is variable depending on application, and can be positioned further towards the first support member 220 or the second end 517 of the third support member. The third support member 515 is sufficiently long to obviate the need for attaching an adjustable prop at the second end 517 of the third support member 515. The third support member 515 has integral means for adjusting its length (not shown) positioned between the location at which the second support member 225 is attached to the third support member 515 and the second end 517 of the third support member 515.

The means for adjusting the length of the third support member comprises a screw and nut assembly, such as the screw and nut assembly found on a typical prop such as the Acrow propTM, or alternatively the means for adjusting the length is hydraulic.

[00076] Fig. 6 shows a fourth example of a wall prop 600. Wall prop 600 is configured and used as described for wall prop 200. Like reference signs in Fig. 6 have like identity and function to like reference signs in Fig. 2.

[00077] A leg 650 is hingedly connected towards the second end 627 of the second support member 625 at hinge 651. The hinge 651 is positioned toward a first end 652 of the leg 650. The leg 650 has a second end 653. The leg 650 can be turned to a direction perpendicular to a wall to be supported, for example wall 205 and the second end 653 passed through an opening, for example the lower hole 236 in the wall 205. Once the whole of the leg 650 and the second end 627 of the second support member 625 have been passed through the wall, then the leg 650 is rotated so that the leg is substantially parallel to the wall 205. The second end 653 of the leg 650 contacts the ground. The leg has integral means for adjusting its length (not shown). In use, the leg 650 supports the second end 627 of the first support member 625 as described previously.

[00078] Fig. 7 shows a fifth example of a wall prop 700. Wall prop 700 is configured and used as described for wall prop 200. Like reference signs in Fig. 7 have like identity and function to like reference signs in Fig. 2.

[00079] In wall prop 700, the rigid connection between the third support member 715 and the second support member 725 is proximal to the second end 717 of the third support member 715. The second support member 725 is configured to be positioned on the ground, obviating the need for props 230 and 240. The third support member 715 has integral means for length adjustment.

[00080] Optionally, wall prop 700 comprises a fourth support member 755 (shown with dashed lines) parallel to the third support member 715. A first end 756 of the fourth support member 755 is rigidly connected to the first support member 220 between the first end 221 and the second end 222 of the first support member 220. A second end 757 of the fourth support member 755 is rigidly connected to the second support member 725 between the first end 726 and the second end 727 of the second support member 725. The fourth support member serves to assist in making the wall prop 700 rigid. The turning moment imparted on the wall prop 700 by the upper section 208 of the wall 205 can thus be negated by the wall prop. Both the third support member 715 and the fourth support member 755 are provided with means for adjusting their length.

[00081] In an example, and as shown in Fig. 7, the second support member is extended by extension 728 (dashed in Fig. 7) to reduce the force required to negate the turning moment imparted on the wall prop 700 by the upper section 208 of the wall 205. The total length of the second support member is greater than the length of the first support member, the extension adds further to the second support member's length.

[00082] Fig. 8 shows a sixth example of a wall prop 800. Wall prop 800 is configured and used as wall prop 800. Like reference signs in Fig. 8 have like identity and function to like reference signs in Fig. 2.

[00083] Wall prop 800 is provided with member 860 to strengthen the rigid connection between the first support member 220 and third support member 215. Member 861 is provided to strengthen the rigid connection between the second support member 225 and the third support member 215. Members 860 and 861 are steel plates welded to the third support member 215, first support member 220 and second support member 225. The members 860 and 861 serve to increase the load bearing capacity and reliability of the wall prop 800. In an example, the members 860 and 861 are triangular steel plates of dimension 225x225x5mm.

[00084] Fig. 9 shows a seventh example of a wall prop 900. Wall prop 900 is configured and used as described for wall prop 200. Like reference signs in Fig. 9 have like identity and function to like reference signs in Fig. 2.

[00085] The first support member 920 is elongated such that a fifth from portion, 965 in the form of a diagonal beam is configured to provide additional support. The elongation of the first support member means that it is rigidly connected to the third support member 915 approximately halfway along its length. A first end 966 of the fourth support member 965 is rigidly connected to the first end 921 of the first support member 921. A second end 967 of the fourth support member 965 is rigidly connected to the third support member 915 between the first end 916 and second end 917 of the third support member 915.

[00086] The fourth support member serves to increase the load bearing capacity and reliability of the wall prop 900. It will be appreciated that additional diagonal beams are provided at the other side of the rigid connection between the third support member 915 and the first support member 920, and for the rigid connection between the third support member 915 and the second support member 225.

[00087] It will be appreciated that the various example wall props shown in Figs. 2 and 4-9 could be combined. For example the wall prop of Fig. 5 could be combined with the pivotable leg of Fig. 6.

[00088] Fig. 10 shows an eighth example of a wall prop 1000. Wall prop 1000 is configured and used as described for wall prop 200. Like reference signs in Fig. 10 have like identity and function to like reference signs in Fig. 2.

[00089] The first support member 1020 is elongated. The first end of 1021 of the first support member 1020 is provided with a fixing for attaching a counterweight (or ground anchor) to balance the weight of the wall 205 positioned toward the second end 1022 of the first support member 1020. This means that the second support member is not necessary. The counterweight is attached to the fixing by a chain or wire. The chain or wire may be provided with means for adjusting the tension thereof.

[00090] The elongation of the first support member means that it is connected to the third support member 1015 approximately halfway along its length. In an example, the distance between the first end 1021 of the first support member 1020 and the connection to the third support member 1015 is greater than the distance between the second end 1022 of the first support member 1020 and the connection to the third support member 1015. This reduces the required mass of the counterweight.

Claims

CLAIMS1. A wall prop for supporting a wall, the wall prop comprising: a first support member extending in a first direction for entering and supporting a wall; and a second support member, spaced from and substantially parallel to the first direction, wherein the first and second support members are rigidly connected, such that the second support member opposes, in use, a turning moment imparted on the first support member by the wall.
2. The wall prop of claim 1, further comprising a third support member, wherein the first and second support members are rigidly connected to the third support member, and wherein the third support member is substantially perpendicular to the first and second support members.
3. The wall prop of claim 2, wherein: the first support member is connected to the third support member towards a first end of the first support member and a towards a first end of the third support member; and the second support member is connected to the third support member towards a first end of the second support member and a towards a second end of the third support member.
4. The wall prop of any preceding claim, further comprising means for acting on the second support member to oppose the turning moment imparted on the first support member by the wall.
5. The wall prop of claim 4, wherein the means for acting on the second support member comprises a prop for supporting the second support member.
6. The wall prop of any preceding claim, further comprising a prop for the third support member.
7. The wall prop of any preceding claim manufactured from reinforced hollow section steel.
8. The wall prop of any preceding claim, wherein the second support member is longer than the first support member.
9. A method of supporting a wall using a wall prop, the method comprising: inserting a first support member of the wall prop into a first hole at least part way in the wall; supporting the prop; removing at least a lower portion of the wall beneath the first hole; and wherein the supporting is such that a second support member of the wall prop opposes a turning moment imparted on the first support member by the wall.
10. The method of claim 9, wherein the first hole does not fully penetrate the wall.
11. The method of claim 10 or claim 11, wherein the first support member is inserted from a first side of the wall, and further comprising: inserting the second member into a second hole at least part way in the wall, wherein the second hole is vertically spaced from the first hole.
12. The method of claim 11, wherein an end of the second support member passes through the second hole to the second side of the wall, further comprising: positioning a prop on the second side of the wall, to support the second support member to oppose the turning moment imparted on the first support member by the wall.
13. The method of claim 12 wherein the second support member is supported by the wall to oppose the turning moment imparted on the first support member by the wall.
14. The method of any one of claims 9 to 13, further comprising: positioning a prop on the first side of the wall to support the wall prop.
15. The method any of claims 9 to 14 using a wall prop according to any of claims 1 to 9.
16. The method of claim 15 dependent on claim 2 wherein the third support member is substantially parallel to the wall.