EP0138259A2 - Drainage structure and method of making a reinforced dike slope - Google Patents

Abstract

The drainage structure is for use in the construction of mainly hydraulic works, particularly but not exclusively for the installation of a dike slope, for the protection against erosion of a foundation block and/or for the production of a filtering or drainage structure used for the discharge or otherwise of quay banks and quay walls. It is formed from blankets or mats (1) which are permeable to water and which have channels or pipes (3) intended to be filled with a material which can be injected into these channels or pipes (3). <IMAGE>

Description

• - constructions de filtre et de drainage dans des structures de mur de quai et de barrage de retenue;
• - constructions de décharge;
• - protection du fond et/ou de talus de digue et/ou de massifs de fondation, comme alternative aux pièces d'épaulement et/ou en zinc connues;
• - construction de renforcement sur un sous-sol à faible force portante.

The present invention relates to new original filter media in their various applications, mainly in hydraulic works, filter fabrics in several thicknesses then taking the form of a carpet and being filled and / or inflated with a material of charge. In particular, although not exclusively, the invention is particularly suitable for the following applications:

• - filter and drainage constructions in quay wall structures and retaining dams;
• - landfill constructions;
• - protection of the bottom and / or embankment embankment and / or foundation blocks, as an alternative to known shoulder and / or zinc pieces;
• - reinforcement construction on a basement with low load-bearing capacity.

Various materials and methods have already been proposed to satisfy the above constructions. These solutions are if not long-term, at least expensive in materials.

The invention therefore aims to eliminate these drawbacks and other known techniques, and to offer a new original product which is particularly suitable for carrying out the above-mentioned soil and hydraulic work.

To this end, the filter block is formed according to the invention by water permeable mats, which have channels or pipes intended to be filled with a material which can be injected or blown into it.

Still according to the invention, said material is in particular formed by expanded clay granules. Preferably, said mats are made of a synthetic material, preferably obtained from an inert synthetic material, in particular: polyethylene and / or polyester and / or polyamide and / or polypropylene.

• La figure 1 est une vue en perspective d'un massif filtrant utilisé lors de la réalisation d'un talus de digue.
• La figure 2 est une vue en coupe verticale d'un talus de digue, avec un massif filtrant incorporé dans le massif de digue.
• Le massif filtrant 1 suivant ces figures est destiné à renforcer un talus de digue 2.

Other details and advantages of the invention will emerge from the description below, given by way of nonlimiting example and with reference to the appended drawings, in which:

• Figure 1 is a perspective view of a filter bed used when making a embankment embankment.
• Figure 2 is a vertical sectional view of a embankment embankment, with a filter bed incorporated in the dike bed.
• The filtering mass 1 according to these figures is intended to reinforce a embankment embankment 2.

It is remarkably suitable for placement during limited time intervals, for example between reflux and flow. It is formed by water-permeable mats or mats, which have channels or pipes 3 which, under the conditions of use, preferably extend from the crest 4 of the embankment slope towards the base 5 thereof. this.

The channels or pipes 3 are closed at the bottom beforehand, while they remain open at the top, until all the channels or pipes 3 have been filled with an appropriate material. The most suitable material consists of granules or grains of expanded clay.

Expanded clay granules, pretreated or not, are remarkably suitable for this use, because they have a temporary floating power. This property can be very useful in certain circumstances.

The filling by injection of the channels or pipes 3 takes place with standard means, from a truck equipped a pump to "blow" the expanded clay granules in each channel or pipe.

The carpets, which may have arbitrary dimensions, may have continuous bands 6 and 7 respectively at the top and at the base, with which they can be anchored relative to the embankment slope.

Depending on local circumstances and needs, the embankment embankment may consist exclusively of a foundation block, but the sand or soil block of the embankment embankment may, as is generally the case, be coated with a thickness of loose stones 8. In this case, the belts 1, as illustrated in the figures, are placed on the loose stones 8, being immobilized at the top and at the base by their bands 6 and 7. In fact, the method Conversely, where carpets or mats are loaded with loose stones or some other spill, is frequently encountered.

When, when carrying out the said work, high and low tides must be taken into account, the carpets are immobilized at low tide or at reflux between the crest 4 of the embankment slope and its foot. The channels or pipes are then filled according to the speed at which the flow occurs, halfway up with the expanded clay granules. Filling up to the height of the ridge of the carpet dike takes place, for example, in a second step. The closure of the channels or pipes, at their upper end, takes place on the spot and with any or any means.

The carpets are then covered, by conventional techniques, with a layer of stones 9. This last layer 9 extends for example from the crest 4 of the dike to the vicinity of its foot. This operating diagram is obviously given only by way of example. Important variations or differences in this operating scheme can also be envisaged.

In some cases, carpets can be filled at some distance from where they are to be used as a trap. these shoulder or foundation, with expanded clay granules. The filled belts can then, thanks to the temporary floating capacity of the granules used, be towed in place. When the expanded clay granules have absorbed enough water, the carpet sinks into the water, so that it can easily be placed in the desired location. This is a very advantageous and original feature of the invention.

It will be obvious that the invention is in no way limited to the above embodiments and that many modifications can be made without departing from the scope of this patent.

Thus, it is clear that the suggested shape and arrangement of the pipes and channels forming part of the carpets used, could offer a completely different design. Dimensions which have been suggested for expanded clay granules are of the size 10/16 mm, because this material can easily be "injected" or "blown" by container and blowing vehicles. The general profile proposed of the carpets and the way in which they are anchored in the embankment slope, are not limiting for the invention.

It is also obvious that the aforementioned channels or pipes can be filled in the workshop, therefore beforehand, partially or completely. Any additional filling then takes place on site.

Claims (8)

1. Filtering mass to be used for carrying out mainly hydraulic works, in particular although not exclusively for the installation of a embankment embankment or the protection against erosion of a foundation mass and / or the realization of '' a filtering or draining block, to discharge or not embankments and quay walls, characterized in that it is formed by water-permeable mats or mats (1) which have channels or pipes (3) intended to be filled with a material which can be injected into these channels or pipes (3). 2. Filtering mass according to claim 1, characterized in that said material is formed by expanded clay granules, for example. 3. Filter media according to either of claims 1 and 2, characterized in that said channels or pipes (3) extend under the operating conditions of the filter media (1), the crest (4 ) at the foot (5) of the embankment slope. 4. Filter media according to any one of claims 1-3, characterized in that said belts (1) have on at least one side, perpendicular to the direction in which extend said pipes or channels (3), a strip (6,7) for anchoring the carpet to the dike. 5. Filter media according to any one of claims 1-4, characterized in that said belts (1) are preferably made from an inert synthetic material. 6. Method for producing a reinforced embankment embankment using filter media according to any one of claims 1-5, characterized in that a carpet as defined in the preceding claims is anchored to a embankment embankment , and the channels or pipes (3) of the carpet (1) are filled with expanded clay granules. 7. Method according to claim 6, characterized in that with variations in existing water level, for example between reflux and flow, partial filling is first carried out. ment at reflux said channels or pipes with expanded clay granules and the filling of these channels or pipes is completed during the flow. 8. A method for producing a reinforced embankment embankment using filter media according to any one of claims 1-5, characterized in that first of all partially filled in the workshop with expanded clay granules a mat as defined in any one of claims 1-5, it is anchored to the embankment embankment and possibly the filling of the channels or pipes (3) of the mat (1) with expanded clay granules.

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