GB2517745A

GB2517745A - Selective filter for impermeable bags used in placing concrete or cementitous material in water

Info

Publication number: GB2517745A
Application number: GB1315479.4A
Authority: GB
Inventors: Andrew Mountain
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-08-30
Filing date: 2013-08-30
Publication date: 2015-03-04
Also published as: GB201315479D0

Abstract

The invention relates to a filter device for use with impermeable sand bag liners or concrete placement bags 5, to allow the placement of dry powdered cement containing bags below water. The device can be attached with a simple snap or threaded fit and forms a fixed filtration device that will allow the controlled movement of water into the bag and also if necessary the controlled movement of air outside, from inside the bag, such that sufficient water for hydration can be absorbed by the dry powdered cementitious material to ensure the concrete hardens. It also allows the trapped air inside the bag to escape without flushing cement fines out of the bag as it escapes, into the surrounding water. The control of cement fines is possible in the device by the incorporation of a filter media 1 or permeable passageway that allows the passage of air and water, whilst assuring the entrapment and non-migration of cement fines.

Description

SELECTIVE FILTER FOR IMPERMEABLE BAGS

USED IN PLACING CONCRETE OR

CEMENTITIOUS MATERIAL IN WATER

DESCRIPTION

Polymer based sandbag liners and biodegradable polymer bags have recently been developed (Patent Number GB2464669) to allow clean placement of concrete in watercourses by providing an impermeable but biodegradable barrier that ensures cement fines stay within the bag until the concrete or other cementitious material has hardened. For wet concretes, a fully impermeable barrier is the cleanest and safest means by which concretes can be placed in rivers or below bodies of water to stop the loss of cement fines into the water body. The liners or bags can also be used with dry materials where water can be added prior to placement and use, to supply sufficient water for hydration of the cement.

The presence of the impermeable barrier does however have the limitation that dry powdered material cannot be placed directly below water, without pre-adding the water, as the impermeable nature of the liner limits or delays the ingress of water into the bag to cure the cementitious material. The liner or bag also prevents trapped air from escaping from inside the bag during placement.

The purpose of the new device is to overcome these limitations by incorporating a fixed point and filter device that will primarily allow the controlled movement of water into the bag and also if necessary the controlled movement of air outside, from inside the bag, in a clean and environmentally acceptable manner, such that sufficient water for hydration can be absorbed by the dry powdered cementitious material to ensure the concrete hardens. It also allows the trapped air inside the bag to escape without cement fines flushing out of the bag as it escapes, into the surrounding water. The control of cement fines is possible in the device by the * incorporation of a filter media that allows the passage of air and water, both of which are of low * .***.

* viscosity and are easier to pass through the filter, and the entrapment of larger more viscous particles of sand and cement fines. This filter media may be in the form of a simple filter pad such as woven or non woven material like a felt pad, consist of filter paper of sufficient gauge to not disintegrate or tear, filter foam, or consist of a more rigid semi permeable disc, pad or membrane such as a porous ceramic or other similar material that allows a considerably slower ingress of water into the bag. The advantage of a rigid semi permeable disc or membrane is that it is less vulnerable to damage and more resistant to the passage of cement fines.

The device is intended to be used in conjunction with impermeable polymer bags or liners and as such added to the bag after the bag has been extruded and manufactured. To add the device to the bag, it is envisaged that either a hole is cut or the device has a perforating or self culling edge to one side, such that then two sides are connected together they sandwich the liner or bag to hold the filter device in place. Connecting the inner and outer sides together can be achieved with a snap or threaded/screw fit connection to the two sides. Gluing the two components is also possible. it is envisaged that the device be formed of plastic or similar easily manufacturable polymer, and the filter component can be positioned on the inside or ouside of the liner or bag used to place concrete or similar cementitious material.

A preferred embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows a snap on version of the device in section Figure 2 shows a possible configuration of one side of the snap on configuration in section Figure 3 shows a possible configuration of the corresponding other side of the snap on configuration in section Figure 4 shows a threaded fit version of the device in section Figure 5 shows a possible configuration of one side of the threaded fit configuration in section Figure 6 shows a possible configuration of the corresponding other side of the threaded fit configuration in section Figure 7 shows a possible configuration of a snap together version showing one side of the device in 3D Figure 6 shows a possible configuration of the corresponding other side of the snap together version in 3D Figure 9 shows the directional passage or water and possibly air through the device in relation to the functioning of the bag and device.

Figure 10 shows an example of the device attached to a bag (empty).

Figure 11 shows an example of the device attached to a bag when filled with concrete. *0*** * .

Figure 1 shows a possible configuration of the device in cross section showing the filter media, 1, held inside an outer body, 2. A separate corresponding body, 3, enables the two parts of the device to connect together to attach to the liner or bag, 5. In this example a self culling edge, 4, to one side of the components is included to cut a hole in the bag or liner, 5. * * **

* Figure 2 shows one side of the device, 6, in cross section, with a recess, 7, in the component to form a simple snap fitting connection to the two sides of the device. The side has a hole, 6, through which water and air can pass through into/out of the bag.

Figure 3 shows the corresponding other side to the device, 9, in section. The filter, 10, is housed inside the component. In this example again, a self cutting edge, 11, is included to cut a hole in the bag or liner. Similarly, it includes a hole, 12, through which water and possibly air can pass.

Figure 4 shows a similar configuration but with a screw attachment to connect the inner and outer parts of the device. The liner or bag, 13, is sandwiched between the inner, 14, and outer components, 16. The figure shows the filter media, 15, housed in the inner component, and similarly utilises a self cutting edge, 17, to pierce the bags. A pàssible configuration of the threaded attachment means is shown 18.

Figure 5 shows one side of the threaded example shown in Figure 5, showing the body, 19, recess and thread, 20, and the opening, 21, through which water and air can pass.

Figure 6 shows the corresponding other side to the threaded example, with the body, 22, filter, 23, housed within the body, self culling edge, 24, hole through which air and water can pass, 25, and the thread, 26, for screw connecting the two sides of the device.

Figure 7 shows a 3 dimensional sketch of a possible configuration of the side of the component housing the filter, in this example a simple push together configuration. It shows the main body of the component, 27, in which is housed the filer, and a self cutting snap together edge, 28.

Figure 8 shows a 3 dimensional sketch of a possible configuration of the corresponding other side of the device showing the main body, 29, with recessed section, 30, into which the snap closing edge (labelled 27 on Figure 7) will fit.

Figure 9 shows a snap close example of the device showing the directional passage of water and air through the device. The liner or bag, 31, incorporates the inner, 32 and outer, 33 parts to the device, forming a connection to the bag or liner. The filter medium, 34, allows passage of water into the bag and air out of the bag, through the hole, 35.

Figure 10 shows an example of the device, 36, attached to an impermeable polymer bag, 37, shown empty.

Figure 11 shows an example of the device, 38, attached to an impermeable polymer bag, 39, * ** * filled with concrete, 40.

Claims

CLAIMS1. A snap on or threaded connecting filter for conversion of polymer sand bag liner or concrete placement bag from impermeable nature to provide a means by which water can enter the bags when submerged and/or air escape slowly and in an environmentally safe manner, allowing the placement of dry powder material below water, incorporating a filter media capable of trapping cement fines and stopping their leak into the surrounding water.
2. A snap on or threaded connecting filter device, as claimed in claim 1, whereby the body of the device is formed from plastic or similar material.
3. A snap on or threaded connecting filter device, as claimed in claim 1 whereby the body of the device is formed from water soluble PVOH polymer.
4. A snapon or threaded connecting filter device, as claimed in claim 1, whereby the filter component consists of a woven, non-woven or foam filter pad or similar, to trap cement fines, preventing their escape into the surrounding water whilst ensuring the passage of water into the bag to hydrate the dry cementitious material.
5. A snap on or threaded connecting filter device, as claimed in claim 1, whereby the filter component consists of a rigid permeable disc, or pad of permeable ceramic or similar permeable material, to allow the slow passage of water into the bag to hydrate the dry cementitious powder material contained within the bag whilst preventing the passage of cementitious mateilal out of the bag.
6. A snap on or threaded connecting filter device, as claimed in claim 1, whereby the filter component consists of a filter paper or thicker card.
7. A snap on or threaded connecting filter device, as claimed in claim 1, whereby the filter component consists of a permeable or semi permeable membrane.
8. A snap on or threaded connecting filter device as herein described above and illustratedin the accompanying drawings or description.* *.*** * * **. . * * * * * ** * * * * * ** *