GB2264974A

GB2264974A - Inflatable tubular shuttering device

Info

Publication number: GB2264974A
Application number: GB9303882A
Authority: GB
Inventors: Owen Gallagher
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-03-11
Filing date: 1993-02-26
Publication date: 1993-09-15
Also published as: GB9303882D0

Abstract

An inflatable shuttering for the formation of concrete channels in culverts and so-called manholes comprises a tubular collapsible member (2) having a rigid spine portion (16) and end portions (6, 8) adapted to be received in respective open end portions (10, 12) of pipe sections, wall portions of said member being of a multi-layer construction permitting the inflation of an annular channel (30) at least substantially between layer (24, 34) of the wall construction. Reinforcing means (36, 38; 58) are provided so that when the device is inflated, there is resistance to deformation and collapse in directions axially and radially of the annular chamber (30) and, when the device is in a deflated condition, the reinforcing means are at least substantially collapsed in a direction radially of the device to permit removal of the device from a formation of settable material moulded thereabout. The reinforcing means may be stiffly resilient or rigid ribs (36, 38) or may comprise a helically arranged inflatable flexible tube (58) arranged in at least substantially contiguous turns within an annular region between layers (54, 56) of said multi-wall construction. <IMAGE>

Description

INFLATABLE TUBULAR SHUTTERING DEVICE The invention is concerned with improvements in or relating to an inflatable tubular shuttering device.

Devices of this kind are particularly, but not exclusively, suitable for use in the in-situ moulding of channels, culverts, tubular pipes and similar liquid carrying passages in concrete or the like mouldable, settable, constructional material.

The invention provides an inflatable tubular shuttering device comprising an at least substantially tubular collapsible member having end portions adapted to be received in respective open end portions of pipe sections, wall portions of said member being of a multi-layer construction permitting the inflation of an annular chamber at least substantially between layers of the wall construction, wherein said wall construction includes reinforcing means adapted to provide, when the device is inflated, resistance to deformation and collapse in directions axially and radially of the annular chamber and, when the device is in a deflated condition, the reinforcing means are at least substantially collapsed in a direction radially of the device to permit removal of the device from a formation of settable material moulded thereabout.

In a first example of the invention, said wall construction includes reinforcing means in the form of stiffly resilient or rigid, longitudinally extending ribs spaced around the wall of the device and held in a substantial parallel manner by suitable means.

In a second example of the invention, said wall construction includes reinforcing means in the form of a helically arranged inflatable flexible tube arranged in at least substantially contiguous turns within an annular region between layers of said multi-wall construction.

Preferably, the inflatable flexible tube provides a convoluted inflatable chamber which may be divided into compartments or sub-chambers for greater degree of control in inflation. Conveniently, the distance between inner and outer walls of the construction may be controlled with the use of regulator means.

Conveniently, said wall construction may include outer walls of proofed or rubberised nylon or similar material having a smooth continuous external surface to facilitate release of the device from the set concrete. The continuous, i.e., non-ridged, surface also results in the formation of a channel or gully which has a smooth surface so that debris or other material from the inlet pipe is not permitted to settle and form a build-up in the channel even where the gradient is very slight.

Preferably, an upwardly facing portion of the shuttering device includes a rigid spine member, conveniently of steel, for connection of the device to a support means within the manhole. Connection means from an air-supply for inflation purposes may also be mounted in the spine member, together with pump means, if necessary, to clear ground water from the concreted area.

There will now be described two examples of devices according to the invention. It will be understood that the description, which is to be read with reference to the drawings, is given by way of example only and not by way of limitation.

In the drawings: Figures 1 and 2 are plan and side views respectively of a first device according to the invention; Figure 3 shows a perspective view, partly cut-away, of the device of Figures 1 and 2 in use in a manhole; Figure 4 is a similar view showing the channel formed by the use of the device; Figure 5 is a view similar to that of Figure 3 showing a branched arrangement; Figure 6 shows the wall construction and supporting arrangement of the device; Figure 7 shows a pump in use in association with the device; Figure 8 shows a second device according to the invention; and Figure 9 is a fragmentary sectional view through a wall construction of the second device.

Figures 1 and 2 show a tubular shuttering device 2 comprising a collapsible tube member 4, end portions 6 and 8 thereof being adapted to be received in open end portions respectively of an inlet pipe 10 and an outlet pipe 12 projecting into a manhole indicated at 14 in Figures 3 and 4.

A rigid spine portion 16, in the present example of steel, is provided on an upper portion of the member 4 and located by straps 18 bonded to the member 4. The spine portion 16 is provided with square sockets 20 adapted to receive support means 21, spanning the manhole 14. The purpose of the device is to act as a former for the laying of a channel or gully to form a continuous flow path for liquids passing through the manhole from the inlet pipe 10 to the outlet pipe 12. A finished channel or gully 22 is shown in Figure 4. The wall construction of the first example is best shown in Figure 5, in which an outer layer 24 is of strong, proofed nylon material which presents a smooth surface to concrete 26 which is poured into the manhole upto a level 28. Within the nylon layer 24 is an annular inflatable cavity 30, the inner wall of which is a rubber tubular wall 32.An innermost wall 34 is also of nylon material in the present example and is re-inforced by the provision of a plurality of lengthwise extending reinforcing ribs 36 of steel or rigid p.v.c., which are maintained in a spaced-apart circumferential layout by suitable means, in the present example by being sewn to the innermost wall 34. Resilient plastics rings 38, which may be attached to the wall 34, also by sewing if desired, are provided to contribute circumferential support to the device.

In use the cavity 30 is inflated through an air valve 40 in valve slot 42 provided in the spine member 16 and adapted to receive compressed air through line 44 (Figure 3).

As may be seen in Figure 5, the device may be provided with a branch-forming tubular means comprising a collar generally indicated by reference numeral 41 for permitting a plurality of channels to be formed in a manhole. The branch collar 41 comprises cylindrical portions 43, 45 adapted to receive the ends of like inflatable devices 2' in the same manner as pipe ends 10 and 12. The branch collar is made of a canvas rubberised structure and the collar is adjustable to suit devices of different diameters.

Thus a complex channel structure may be made using inflatable devices and a branch collar 41 of the type shown in Figure 5. It will be appreciated that inlet pipes 12 are coupled to the outlet pipe 10 via channels constructed by using the construction shown in Figure 5.

The operation according to this arrangement is the same as shown in Figure 1 and Figure 2, i.e. when the inflatable shutters have been positioned and inflated, the concrete is then poured to a predetermined level. When the concrete has set, the devices are deflated and removed together with the collar to leave drainage channels of generally U-shaped cross-section.

In either case, when concrete is poured, the arrangement is left until it has set, but during this time, liquid flow through the device 2 can take place through the passageway provided by the innermost wall 34.

It will be appreciated that the cross-sectional area of the passageway is not restrictive being only a little less than that of the device itself and indeed is greater than that of the finished channel 22. When the concrete has set, the device 2 may be deflated and collapses radially so that it may be removed for re-use, the channel or gully 22 then taking the flow from the inlet pipe 10.

Figure 7 shows a small pump arrangement 46 which is a 110 volt lift pump in the present example. A pipe 48 is arranged below the level of any water present in the manhole 14 to keep the area as free from water as possible. The pump 46 operates to drain the water so that setting of the concrete is not hindered. Conveniently the water pumped by the pump 46 is directed into the through flow of liquid within the device by means of a pipe 50 through a gas-tight seal 52.

A second example of a device according to the invention is similar to the first device in all respects except the construction of the wall of the member 2.

Figure 8 shows a member, referred to as 2" for convenience, in which a spine portion 16' is secured to an outer layer 54 of proofed nylon. The member 2" further comprises an inner layer 56 also of proofed nylon.

Received in the annular space between the two layers 54 and 56 is a helical, inflatable, flexible tube 58 arranged in substantially contiguous turns or coils 60 so that when the tube 58 is inflated under working pressure, the device 2" is substantially rigid in both the axial and radial directions. When, after use, the concrete has set, deflation of the device results in the collapse and deformation of the member 2" in both axial and radial directions, thereby facilitating its removal from locations which present access difficulties. This facility would be particularly useful for use in the replacement of decayed brickwork by poured concrete in existing sewers and the like. It will be understood that the dimensions of the device will be selected according to the location in which it is to be used.

Various modifications may be made within the scope of the invention.

Claims

CLAIMS:

1. An inflatable tubular shuttering device comprising an at least substantially tubular collapsible member having end portions adapted to be received in respective open end portions of pipe sections, wall portions of said member being of a multi-layer construction permitting the inflation of an annular chamber at least substantially between layers of the wall construction, wherein said wall construction includes reinforcing means adapted to provide, when the device is inflated, resistance to deformation and collapse in directions axially and radially of the annular chamber and, when the device is in a deflated condition, the reinforcing means are at least substantially collapsed in a direction radially of the device to permit removal of the device from a formation of settable material moulded thereabout.

2. A device as claimed in claim 1, wherein said wall construction includes reinforcing means in the form of stiffly resilient or rigid, longitudinally extending ribs spaced around the wall of the device and held in a substantial parallel manner by suitable means.

3. A device as claimed in claim 1, wherein said wall construction includes reinforcing means in the form of a helically arranged inflatable flexible tube arranged in at least substantially contiguous turns within an annular region between layers of said multi-wall construction.

4. A device as claimed in claim 3, wherein the inflatable flexible tube provides a convoluted inflatable chamber which may be divided into compartments or sub-chambers for greater degree of control in inflation.

5. A device as claimed in claim 4, wherein the distance between inner and outer walls of the construction is controlled by means for regulating the number of compartments or sub-chambers to be inflated.

6. A device as claimed in any one of the preceding claims wherein said wall construction includes outer walls of proofed or rubberised nylon or similar material having a smooth continuous external surface to facilitate release of the device from the set concrete.

7. A device as claimed in any one of the preceding claims, wherein an upwardly facing portion thereof includes a rigid spine member for connection of the device to a support means within the manhole.

8. A device as claimed in claim 7, wherein said spine member provides mounting for an air supply.

9. A device as claimed in either one of claims 7 and 8, wherein said spine member provides mounting for a pump.

10. A device as claimed in any one of the preceding claims wherein there is provided a branch forming tubular means comprising a plurality of first cylindrical collar portions each adapted to receive an inflatable device so as to provide a plurality of inlet channels and a further cylindrical collar portion adapted to form an outlet channel.

11. An inflatable tubular shuttering device, constructed and arranged substantially as hereinbefore described with reference to and as shown in the drawings.