WO2014076392A1

WO2014076392A1 - Pre-fabricated bituminous sealing membrane or geomembrane

Info

Publication number: WO2014076392A1
Application number: PCT/FR2013/052662
Authority: WO
Inventors: Renaud BENCHET
Original assignee: Icopal Sas
Priority date: 2012-11-19
Filing date: 2013-11-07
Publication date: 2014-05-22
Also published as: FR2998313A1; FR2998313B1

Abstract

The invention relates to a bituminous sealing membrane (1) comprising, on at least one of the edges thereof, an element (2) built into a face of the membrane and used to form a channel once the membrane is in place on a surface to be sealed, said element (2) being gas-permeable and consisting of at least one part made of a flexible material and impervious to molten bitumen. According to the invention, said membrane is pre-fabricated, said element being fixed to said face of the membrane before it has been placed on the surface to be sealed.

Description

MEMBRANE OR SEALING GEOMEMBRANE

PREFABRICATED BITUMINOUS

The invention relates to a membrane or prefabricated bituminous waterproofing geomembrane, particularly for buildings, structures, buried structures, hydraulic structures or environmental protection works.

By bituminous membrane, it is understood, in the following, a bitumen-based membrane or a geomembrane based on bitumen. Such membranes are generally in the form of strips or strips of a length of 5 to 100 m and width of between 0.2 and 4 m, packaged in roll.

The prefabricated bituminous sealing strips are tightly assembled by overlapping one strip on the other and welding with a propane torch or with hot air over a width of between 5 and 20 cm and these areas or joints of overlap must have a seal equivalent to that of the entire band. However, this sealing of the overlapping edges is currently in practice uncontrollable after execution.

There are also plastic sealing strips, for example PVC, HDPE, PP, TPO or LDPE, whose cover joints are welded using hot air machines generating two very close welds forming between them a channel for checking the tightness of the welds by injection of pressurized air inside this channel. The other end of the channel being clogged, it controls, via a manometer, the injected air pressure. If the pressure is maintained, it is that there is no leakage and that the weld is well done and therefore waterproof. If the pressure is not maintained, there is one or more leaks and therefore the welding is not properly performed and therefore not waterproof.

A simple transposition of this embodiment of a sealing control channel to prefabricated bituminous membranes and geomembranes is impossible. Indeed, because of their rheology and hot melt assembly mode of the bitumen of each membrane by gas flame or hot air, the bitumen becomes liquid and a channel thus formed would be at least largely destroyed or filled, when making the joint.

The invention proposes a solution for adapting and applying this mode of control by air pressure to a bituminous membrane.

Patent documents JP H04 80452 and JP 2004 351635 describe such a control mode applied to a bitumen membrane.

An element intended to form a channel is placed on a bituminous waterproofing membrane at one of its edges, in situ on site, during the establishment of the membrane on a surface to be sealed. This element is permeable to gases and consists of at least a portion of flexible material and impervious to bitumen.

Such an embodiment in situ is relatively long and complex to implement manually or requires specific tools.

The invention solves this problem by means of a membrane arrangement which facilitates the installation allowing this mode of control of the air pressure seal.

To do this, the invention proposes a bituminous waterproofing membrane comprising at least at one of its edges an integrated element on one side of the membrane and intended to form a channel, once the membrane is put in place on a surface with to seal, this element being permeable to gases and consisting of at least a portion of flexible material and impervious to molten bitumen, characterized in that said membrane is prefabricated, said element being fixed on said face of the membrane before laying it on the surface to be sealed.

Preferably, said element is fixed on said face of the membrane at the factory.

According to a preferred embodiment, said material is flame retardant at a temperature of at least 300 ° C.

Said material is advantageously a glass woven fabric coated with a flame retardant elastomer.

It is thus possible to produce a flat channel element which can be easily marouflaged which ensures a quality of welding of the waterproofing membranes.

Preferably, said elastomer is silicone.

Advantageously, according to a variant, said element is formed of two strips of said material superimposed and stitched together at their longitudinal edges.

Each band may have a width of between 1 and 3 cm.

According to a second variant, said element is formed of a strip of said material folded and stitched at its longitudinal edges.

Said strip may have a width of between 2 and 6 cm. Preferably, said integrated element is disposed at a single longitudinal edge of the membrane.

Advantageously, said integrated element is disposed on the upper face of the membrane

The invention is described below in more detail with the aid of figures representing only a preferred embodiment of the invention.

Figure 1 is a view showing a membrane according to the invention.

FIG. 2 is a view showing an element integrated into a membrane according to the invention. Figure 3 is a partial vertical sectional view of two membranes according to the invention placed on a surface to be sealed.

FIG. 4 is a view from above of several membranes in accordance with the invention placed on a surface to be sealed.

As represented in FIG. 1, a bituminous waterproofing membrane 1 according to the invention, in the form of a strip, preferably has at one of its longitudinal edges 1A an integrated element 2 on the upper face of the membrane and intended to form a channel once the membrane disposed next to another membrane on a surface to be sealed.

Still according to the invention, this integrated element 2 may also have a non-longitudinal edge or two longitudinal edges of the membrane. It can also be placed on the underside of the membrane.

This element 2 is gas permeable and consists of at least a portion of flexible material and impervious to molten bitumen and is fixed on the face of the membrane, preferably by melting the bitumen at its attachment. Preferably, this material is flame retardant at a temperature of at least 300 ° C corresponding to the laying temperature and welding of a lap joint.

FIG. 2 represents a preferred embodiment of this integrated element 2.

This element 2 is formed of two strips 2A, 2B superimposed and stitched together at their longitudinal edges by a seam 2C, 2D.

These strips 2A, 2B are of flexible material, flame retardant at a temperature of at least 300 ° C and impervious to molten bitumen. This material is preferably a glass woven fabric coated with a flame retardant elastomer, preferably silicone. Each band preferably has a width I of between 1 and 3 cm. By way of example, these strips 2A, 2B consist of a glass satin with a thickness of about 0.4 mm.

The yarn seams 2C, 2D is preferably in turn a heat-resistant material, in particular the flame of the propane torch used for welding sealing membranes. This sewing thread may for example be stainless steel, glass, carbon or aromatic polyamide.

Alternatively, the element 2 may consist of a single portion of flexible material, for example a strip of the same material but double width 2x1, this band being folded longitudinally along its median axis and stitched at its free edges.

The laying of such membranes on a surface to be sealed is illustrated in Figure 3 which partially describes two membranes 1, 1 'according to the invention.

The first membrane 1 is placed on this surface to be sealed and therefore has its integrated element 2 on its upper face substantially on the central axis of a covering zone D. To form the sealing coating, a second membrane is placed next to this first membrane 1 with a cover gasket D. At this overlap, the two membranes 1, l 'are welded with the torch or hot air by melting their bitumen Bl, B2 on the upper face of the first membrane 1 and the lower face of the second membrane 1.

The integrated element 2 is essentially formed of a material resistant to a temperature of at least 300 ° C and impervious to molten bitumen, it is neither damaged nor destroyed during this welding. Only the seam thread is possibly burned if it is in current material, the integrated element 2 then being gas permeable through these seams.

To form a complete coating, a plurality of such membranes are thus laid in a "flake-type" conformation. As has been seen above, the integrated element 2 can also be arranged at the two longitudinal edges of the membrane 1. In this case, the first membrane 1 is a membrane according to the invention with two integrated elements 2 and the second The membrane is a conventional membrane without integrated element 2. To form a complete coating, a plurality of such membranes are thus laid alternately.

As has also been seen above, the integrated element 2 can be arranged on the underside of the membrane and, according to the configuration of FIG. 3, the edge of the first membrane 1 is devoid of integrated element 2 and the edge of the second membrane to be provided with an integrated element 2.

The process for checking the tightness of a bituminous coating, consisting of at least two prefabricated bituminous waterproofing membranes 1, laid with a lap joint D of one of their edges as shown in FIG. consists in injecting gas under pressure into the integrated channel element 2.

The integrated element 2 is disposed between the two membranes 1, 1 'in the cover gasket D and a pressurized gas, preferably air at a pressure of between 1 and 4 bar, is injected into the channel in one direction. point of the lap joint, one of the ends of the channel being closed, the pressure of this gas being controlled, a decrease in the pressure detecting a sealing problem in said lap joint.

This point can be a free end inlet of the channel at the edge of the membrane equipped with an integrated element 2 or be any point of the lap joint D, the gas then being injected through one of the strips 2A of the integrated element 2 for example by means of a needle. According to this method, it is thus easy to check the tightness of the seal over a membrane length or even over a corresponding upper length to several lengths of aligned membranes. In the latter case, the integrated element 2 of two aligned membranes are connected for example by stapling.

Furthermore, thanks to the invention, the integrated element 2 is neither visible nor in contact with the environment disposed above the sealing membrane, for example water in the case of a seal basin.

The end of the channel closure necessary to avoid this contact and also to allow control by pressurizing gas is performed by means of a prefabricated bituminous sealing piece welded to this end.

By way of example, FIG. 4 illustrates an implementation of such a closure piece.

Figure 4 illustrates the example of three adjacent membranes, laterally and longitudinally, according to the invention, placed on a surface to be sealed.

A first membrane 1 is placed and at its end E, its integrated element 2 is peeled over a length of 20 to 30 cm and this peeled length is cut with the cutter.

A second membrane perpendicular to another membrane 1 "'provided with an integrated element 2"' is placed at the longitudinal end of the first membrane 1 with a transverse overlap zone D of longitudinal ends and, when the realization of this joint, a discontinuity is made between the end of the integrated element 2 'of this second membrane 1' and the cut end of the integrated element 2 of the first membrane 1. This discontinuous zone allows the closing of the ends of the corresponding integrated elements 2 and 2 'at this location during the production of the zone of recovery performed between the first and second membranes 1, the and the other perpendicular membrane 1 ".

A third adjacent membrane 1 "is then placed with a longitudinal overlap zone D with the two preceding membranes 1, This longitudinal overlap zone D is therefore identical in conformation to the section shown in FIG. 3, the first and second membranes 1 , having their integrated element 2 visible on their upper face.

A piece of bituminous membrane 3, for example square, with a length of the order of 30 cm, is bonded by melting the bitumen at the free end of the second membrane 1 in order to close and seal the channel formed by the element 2 'carried by the second membrane the.

Thus the control of the seal can be achieved by injecting gas into the integrated element 2 'or 2 at any point of the lap joint D.

Claims

1. A bituminous waterproofing membrane (1) comprising at least at one of its edges an integrated element (2) on one side of the membrane and intended to form a channel, once the membrane is placed on a surface to be sealed , this element (2) being gas permeable and consisting of at least a portion of flexible material and impervious to molten bitumen, characterized in that said membrane (1) is prefabricated, said element (2) being fixed on said face of the membrane before laying it on the surface to be sealed.

2. Membrane according to claim 1, characterized in that said material is a glass woven coated with an elastomer.

3. Membrane according to claim 2, characterized in that said elastomer is silicone.

4. Membrane according to one of the preceding claims, characterized in that said element (2) is formed two strips (2A, 2B) of said material superimposed and stitched together at their longitudinal edges.

5. Membrane according to the preceding claim, characterized in that each strip (2A, 2B) has a width of between 1 and 3 cm.

6. Membrane according to one of claims 1 to 3, characterized in that said element (2) is formed of a strip of said material folded and stitched at its longitudinal edges.

7. Membrane according to the preceding claim, characterized in that said strip has a width of between 2 and 6 cm.

8. Membrane according to one of the preceding claims, characterized in that said integrated element (2) is disposed at a single longitudinal edge of the membrane (1).

9. Membrane according to one of the preceding claims, characterized in that said integrated element (2) is disposed on the upper face of the membrane.