Device for stabilizing bulk material, especially soil masses

Description

Field of the invention

[0001] The present invention relates to a device, generally for stabilizing bulk material and more specificly for stabilizing soil masses, comprising a substantially elongated web which in mounted position defines a plurality of cells or pockets.

[0002] The invention also relates to a method for stabilizing bulk material, especially soil masses.

[0003] The invention also relates to a special use of such a device.

State of the art

[0004] In connection with stabilizing soil masses and especially slopes, it is previously known various products. For example there may be used a net which is made from plastics or steel wire. These types of nets will function satisfactorily provided the slope is not too inclined and provided the soil masses are not influenced by heavy rain before the planting of bushes or similar.

[0005] Another type of device for stabilizing soil comprises plastics plates which are streched in both directions after first having been provided with holes. Examples of such plates are known from Norwegian Patent Specifications 134 995, 152 611 and 152612.

[0006] It is true that the stretching of the plates or the webs results in a net configuration which has a larger depth or thickness than usual flat wire netting, but they do not provide an earth stabilizing effect in the form of stage-wise arranged pockets.

[0007] DE-A 1 915 523 discloses another type of soil stabilizing device and such includes slotted sheet material inteded on stretching to form undulating soil engaging projections. Still another product comprises multi-edged cells which together define an element. These elements can be interconnected to cover a slope, the elements having a certain height, for example 90 mm., a fact which makes it possible for the elements to hold a substantial amount of soil also in slopy terrain. However, the production of such elements involves not only a larger quantity of plastics material but also a more costly production as such. Besides, the elements require a large volume during transport, a fact which involves higher transport expences even if the elements to a certain degree can be stacked on top of each other.

[0008] Further, there are known so-called semi-rigid, three-dimensional geotextiles of honeycomb type made from non-woven polyester for stabilizing the top layer of road embankments, river-banks and similar. This type of stabilizing device can be transported in collapsed form and is easy to put into position on the site of use. However, the production of such geotextiles is very sophisticated and costly, the product itself being too soft for rendering a sufficient anchoring effect in the ground onto which it is to be mounted. Besides, the walls of the cell structure of the completely installed geotextile will extend under a right angle from the plane of the ground, also when an inclined slope is the case, a fact which involves that the soil which has been filled into the cells and is to be stabilized, more easily will flow out of the cells or pockets due to heavy rain showers.

General description of the invention

[0009] The object of the present invention is first of all to give instructions for a device for stabilizing soil masses, and then a device which does not suffer from the disadvantages inherent in the prior art devices, the favourable caracteristics thereof being preferably retained.

[0010] In other words, according to the invention it is aimed for a soil stabilizing device conforming to the following requirements:

I. It is to be manufactured from relatively inexpensive raw material.

2. The speed of disintegration should be varied, from for example easily decomposable in connection with soil areas which are easily overgrown, to a disintegration which takes place over several years.

3. The process of manufacture should be simple and preferably based on prior art.

4. The device should require a small transport volume and the mounting on the site should be simple.

5. The device should have an inherent good faculty of anchoring.

6. The cells or the pockets which are formed during mounting should have walls which possibly can be regulated, and which preferably should extend vertically independent of the inclination of the slope to optimize the stabilizing effect on the occurance of heavy rain showers.

[0011] According to the invention the above requirements are met in connection with a device of the type stated in the preamble, which is characterized in that the web is constituted by an initially relatively thin, substantially plane web, preferably made of bendable plastics, which in one direction is provided with rows of subsequently arranged slits which are so staggerd relative to each other that the web when being stretched transversly relative to the slit form oppositely undulated strips which through a suitable mounting define side by side arranged cells or pockets. By spreading the transversely stretched device on a slope, the cells or pockets can be filled with soil which is to be stabilized by the device.

[0012] In other words, a flat web is taken as a basis for the present device, said web being provided with the above stated slits, and allowing for production in larger or lesser rolls for storage and transport. Thus, the web can be transported to the place of use in rolls rendering a minimum transport volume. Only at the site, i.e. after the web has been spread out on the ground and has been stretched in the direction transversely to the slits, there will be formed upwardly extending backs or walls, which in turn form pockets which stabilize the soil which after the stretching is filled into the pockets of the device. The web can then in advance have been cut in apropriate lengths depending on the landscape or the ground which is to be prepared for soil stabilizing.

[0013] During the mounting of the device, this is not subjected to any permanent deformation, since the soil masses which are filled into the pockets will keep the web in position in "stretched" condition.

[0014] Another special feature of the present device is related to the small thickness of the web, the stretching thereof implying that sharp lower edges appear along the undulating strips, and said sharp edges can easily be pressed into the ground when mounting the web on the site, a fact which entails a secure anchoring of the device even in steep slopes.

[0015] A further feature of the present device is to the fact that by various degrees of stretching there can be achieved various mutual angles between the wall portions of the undulated strips, and that various degrees of stretching can be used for various slope angles of the ground which is to carry the device. Various degrees of stretching will also give different sizes of the cells or pockets, giving larger possibility of selecting a device structure depending on the shape of the terrain.

[0016] Alternatively, the device may be placed on a support and serve as a guard for sand, snow or similar.

[0017] In the area of each slit there may be provided an edge area taking the form of bulging or embossment, which in connection with the stretching will ensure that the undulation of the corresponding strip portions takes place in the right direction relativ to other strip portions.

[0018] To achieve a correct direction of the undulation of the strips during mounting of the device according to the invention, the plastics web may during the production thereof while still being soft and hot, be subjected to an initial stretching transversly to the slits. This initial stretching may be effected so far that the individual strip portions have embedded thereinto a "thermal memory", or a permanent initial plastic deformation which is to point out the direction in which the strip portions are to undulate during the final and complete stretching of the web on site.

[0019] For example, the "thermal memory" or the initial stretching may be effected in the area of the slits, for example by means of combined slitting and pressing rollers.

[0020] This small pre-stretching will give some bulging of the said strip portions, especially in the area of the slits, but the flexible web will still be substantially flat and can thus be tightly rolled up in rolls for storage and transport.

[0021] Possibly, the slits may at each end be provided with curved portions for resisting breakage when the web is stretched.

[0022] Further, the web may be laminated with a suitable woven or knitted cloth, especially for reinforcing the end portions of the slits.

[0023] Preferably the web is manufactured from plastics, for exam ple polyethylen. Suitable additives to the plastics may vary the resistance agianst decomposition.

Brief description of the drawings

[0024] The invention will in the following be further disclosed with reference to the attached Figures illustrating embodiments and fields of application for the present stabilizing device.

[0025] 

Fig. I is a schematic plan view of a web forming the basis of an embodiment of the present device.

Fig. la is a section of a web according to the invention, whereas

Fig. Ib is an enlarged section of an area of the device according to Fig. la.

Fig. 2a is a perspective view illustrating the various phaces of the stabilizing process in which the device according to the invention is to be used, the upper part of the Figure illustrating the device in mounted position, the center portion of the Figure illustrating the device covered with soil material, and the lower portion of the Figure illustrating the stabilized area after a growing season.

Fig. 2b is an enlarged fraction of the area indicated in Fig. 2a.

Fig. 3 illustrates on a larger scale a fraction of a section through the device according to Fig. 2a as seen in the direction III-III in Fig. 2a.

Description of preferred embodiments

[0026] In Fig. I which illustrates schematicly a top view of a web which forms the basis of an embodiment of a device according to the invention used as a soil stabilizing device, the web itself is designated by reference numeral I, the web appropriately being manufactured through an extrusion or calender process of a plastics material to a web having a thickness from for example 0.1 to 6 mm. The thin substantially plane web I of preferably flexible plastics material is during the manufacturing provided with rows of consequtively arranged slits, for example by punching or slitting, the slits 2 in the first row being arranged substantially with even spacing, whereas the slits 2a of the adjacent row is arranged with the same spacing but staggert relative to the slits 2 of the first row. The next row of slits 2b are provided parallel to the slits 2 of the first row, and there is in this way provided a slit pattern which by an appropriate stretching of the web I creates op- positily undulating strips 3a,3b,3c etc., as this is specially appearent from Fig. 2a.

[0027] The plastics web which in Fig. I is designated by I, is during the manufacturing thereof slitted or punched, so as to comprise a plurality of rows of slits 2,2a,2b etc., the number of rows being chosen according to the field of application of the finished manufactured web. Thus, the web can be manufactured in desired width and can be delivered as rolls or as individual web-shaped plates. In Fig. la there is shown a section of a web I which has been rolled or spread out on a support onto which the soil masses are to be stabilized. If the slits are made transversely to the production line direction of the web and the web is rolled up in this direction, a web which is rolled out on site will there be stretched in the longitudinal direction, i.e. in the same direction as the rolling out.

[0028] When the plastics foil or plastics web I has been rolled out or spread out on a support, for example a sloping ground 4, as this appears from Fig. 2a, there will by appropriate stretching of the web I as symbolized by the arrow P in Fig. la, be provided oppositely undulating strips 3a,3b,3c. These strips will have alternating concave and convex portions 5 and 6, respectively, as a result of the slits 2,2a,2b, whereas at the interconnected web zones retained between the slits, here the zones 7, here will have a relatively straight form. In other words, there are provided side by side arranged or stage-shaped cells or pockets 8 which can be filled with soil which is stabilized by the device I.

[0029] At the top of Fig. 2a there is shown a fraction of a web I which has been stretched transversly to the slits, and which has been placed on a sloping ground 4, for example of soil or gravel, whereas in the middle of Fig. 2a it is shown how the cells or the pockets 8 have been filled with soil 9 which is stabilized by the device I. The stretching gives the web I a substantially non-permanent deformation which however will be retained by the filling of soil mass 9. The upwardly extending backs or walls of the undulations 3a,3b, 3c do not only form pockets 8 but also render a favourable anchoring due to the sharp lower edges 10 which bury themselves fairly well into the ground, as this is especially illustrated in Fig. 2b.

[0030] Because the web I in its stretched condition can be pressed deeply into the ground, it will not slide even in steep slopes. This condition is eve better illustrated in Fig. 3, in which the device I is pressed down into an especially steep hill 4a, and in which the walls of the undulations 3a,3b,3c will still extend vertically from the ground for the forming of cells or pockets 8 having vertical backs or walls. This vertical arrangement of the backs or the walls will aside from rendering a favourable anchoring also give an especially good stabilization of the soil 9 and the pockets during heavy rain.

[0031] As appearing from fig. Ib there may in the area of each slit 2,2a,2b etc. be arranged bulge or embossing II, which during the stretching of the web I will aid in that the corresponding stip portion will undulate in the correct direction relative to other strip portions.

[0032] An alternative way to have the individual strip portion undulate in the correct direction during the stretching of the web on site, is to the fact that the plastics web when this is still soft and hot during the production thereof, is subjected to an introductory stretching in the area of the slits, as this is further disclosed in the preamble of the specification.

[0033] In Fig. la there is also illustrated a fixing peg 12 which during the speading of the web I on a sloping ground 4, is inserted through a slit 2 below the upper strip 3a, the peg 12 at its lower end being provided with barbs 12a serving for the attachement to the ground, and which at its upper portion is provided with arms 12b for supporting the upper strip 2 when the web I is stretched out as illustrated in Fig. 2a.

[0034] At the bottom of fig. 2a it is shown how the landscape, in which is utilized the soil stabilizing device according to the invention, can appear after a growth season, the top of the soil 9 now being overgrown by a lawn 13 having its roots extending down into the soil 9.

[0035] It is to be understood that in the openings or the pockets 8 in the web I there can also be planted bushes or similar, all in dependence of the landscape which is to be shaped by means of the soil stabilizing device.

[0036] The material from which the web I is to be manufactured, can for example be a plastics material filled with carbon black, a fact which renders the plastics very resistant to decomposition. Possibly, the plastics may be manufactured without any fillers or be mixed with pigments making the web chemically instable, a fact which involves that the plastics will disappear after some years out in nature.

[0037] If there is used a thicker plastics web as a soil stabilizing device it may be necessary to use mach- anical power for the stretching thereof. This may in some cases be necessary, but the web is preferably manufactured as a flexible plastics web which can be stretched on site by means of manual force.

[0038] Possibly it may in connection with thicker plastics webs be used heat treatment, such that the plastics in its stretched condition will retain its stretched configuration, and the web could then be used for heavier stabilizing objectives, for example stabilizing temporary roads or areas, military airports or similar.

[0039] Alternatively, the present device can be mounted on a support to serve as a guard for sand, snow or similar.

[0040] In this connection it may be appropriate to use a somewhat thicker web which is stretched on a rack or rail or between poles which are located along a railway or a road being especially exposed for the accumulation of whirling snow or sand. By means of the present device the snow or sand particles could be guided so as to be collected in snowdrifts or sandheaps where they are apt to make the least damage, respectively are to least inconvenience.

[0041] It is to be understood that the device according to the invention also can be used as awning, for example for protection against sunshine, light, radiation etc.

[0042] Of course it can in this connection be used materials of various quality, colour, translucence etc. The device can then be pre-mounted on a frame which can be mounted in position on the site where it is to be used.

Claims

1. Device, especially for stabilizing bulk material, comprising initially relatively thin, substantially flat web (1), preferably of flexible material, which in a first direction is provided with rows of consecutively arranged slits, (2, 2a, 2b etc.) which are staggered relative to each other, characterized in that in the area of one or more slits (2, 2a, 2b) there is provided a bulge or embossing (11) which during the stretching of the web serve for the undulating of the corresponding strip portion in its right direction relative to the other Strip portions, so that the web (1) after the stretching thereof forms oppositely undulating strips (3a, 3b, 3c) defining side by side arranged cells or pockets (8) which can be filled with soil which is stabilized by the device (1).

2. Device as claimed in claim 1, characterized in that the web (1) comprises a "thermal memory" or an introductory transverse stretching which is effected during the production of a plastics web, and which will initiate the direction in which the strips are to undulate during the final stretching on site.

3. Device as claimed in claim 1 or 2, characterized in that the "thermal memory" or the initial stretching may be effected in the area of the slits, for example by means of combined slitting and pressing rollers.

4. Device as claimed in any of the claims 1-3, characterized in that the oppositely undulating strips (3a, 3b, 3c) which are formed by the stretching of the web (1) comprise undulating edge portions (1) which can easily be pressed down into the ground (4) and thereby ensure anchoring of the device (1) on site.

5. Device as claimed in any of the claims 1-4, characterized in that various degrees of stretching of the web (1) renders various mutual angles between the wall portions of the oppositely undulating strips (3a, 3b, 3c), so that various degrees of stretching can be used in dependence of the sloping angle of the ground (4) which is to carry the device (1 ).

6. Device as claimed in any of the preceding claims, characterized in that at the ends of the slits (2) of the web (1) there are provided curved portions to resist breakage when the web (1) is stretched transversely relative to the slits.

7. Device as claimed in any of the preceding claims, characterized in that the web is laminated with a suitable woven or knitted cloth for further reinforcement of the end portions of the slits (2).

8. Device as claimed in any of the preceding claims, characterized in that the web (1) is manufactured from plastics, for example polyethylene.

9. Method for stabilizing bulk material, especially soil masses, including the use of a relatively thin, substantially flat web (1) preferably of flexible material, which in a first direction is provided with rows of consecutively arranged slits (2, 2a, 2b), the web in suitable ringlets being spread out on a flat or sloping ground (4) which is to be soil stabilized, characterized in that there is used a web (1) during its manufacture provided with bulges or like means (11) which ensure a predetermined undulation of strips (3a, 3b, 3c) when said web (1) is stretched in a second direction (3a, 3b, 3c), that the web after being spread out on the ground (4) at its one longitudinally extending edge being attached to the ground (4) by means of appropriate fixing means (12), and that the web (1) thereafter is stretched in the second direction of the forming of oppositely undulating strips (3a, 3b, 3c) which in turn define side by side arranged cells or pockets (8) which can be filled with soil which is stabilized by the device (1).

10. Method as claimed in claim 9, characterized in that the web (1) after the stretching will have its lower edge portions (1) of the individual undulated strips, (3a, 3b, 3c) pressed into the ground (4) for anchoring of the device (1) in the ground (4).

11. Method as claimed in claim 9 or 10, characterized in that the web (1) on the site of use is stretched in the second direction for through non-permanent deformation to define said cells or pockets (8), the deformation being retained by the filling of soil (9) in said cells or pockets (8).

12. Method as claimed in claims 9 to 11, characterized in that the web (1) in a suitable length is attached to a rack along one of its end edges, and that the web (1) is thereafter stretched in a direction for the forming of oppositely undulating strips (3a, 3b, 3c) which in turn define side by side arranged cells or pockets (8) serving to guard against whirling sand, snow or similar.

13. The use of a device as claimed in one of the claims 1-8 as an awning, for example for protection against sunshine, light, radiation etc.

Ansprüche

1. Vorrichtung, insbesondere zum Stabilisieren von Schüttgütern, mit einem ursprünglich verhältnismässig dünnen, hauptsächlich flachen Gewebe (1), vorzugsweise aus flexiblem Material, das in einer ersten Richtung mit Reihen von hintereinander angeordneten, gegenseitig versetzten Schlitzen (2, 2a, 2b etc.) versehen ist, dadurch gekennzeichnet, dass im Bereich eines oder mehrerer Schlitze (2, 2a, 2b) eine Ausbauchung oder Prägung (11) vorgesehen ist, die beim Strecken des Gewebes dazu dient, das entsprechende Streifenteil in der rechten Richtung gegenüber den anderen Streifenteilen zu wellen, so dass das Gewebe (1) nach dem Strecken desselben entgegengesetzt gewellte Streifen (3a, 3b, 3c) bildet, die Seite an Seite angebracht Zellen oder Taschen (8) bilden, die mit durch die Vorrichtung (1) zu stabilisierendem Erdreich gefüllt werden können.

2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass das Gewebe (1) ein "eingefrorenes thermisches Rückstellbestreben" oder eine anfängliche Querstreckung aufweist, das/die während der Herstellung eines Kunststoffgewebes bewirkt wird und die Richtung einnimmt, in der die Streifen bei der endgültigen Streckung an Ort und Stelle zu wellen sind.

3. Vorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass das "eingefrorene thermische Rückstellbestreben" oder die ursprüngliche Streckung im Bereich der Schlitze bewerkstelligt ist, beispielsweise durch kombinierte Schlitzungs-und Pressrollen.

4. Vorrichtung nach einem der Ansprüche 1-3, dadurch gekennzeichnet, dass die durch das Strecken des Gewebes (1) entgegengesetzt gewellten Streifen (3a, 3b, 3c) Wellenbögen (1) aufweisen, die leicht in den Erdboden (4) eingepresst werden können und dadurch ein Verankern der Vorrichtung (1) im Erdreich sicherstellt.

5. Vorrichtung nach einem der Ansprüche 1-4, dadurch gekennzeichnet, dass verschiedenes Strecken des Gewebes (1) zu verschiedenen gegenseitigen Winkeln zwischen den Wandteilen der entgegengesetzt gewellten Streifen (3a, 3b, 3c) führen, so dass unterschiedliches Strecken in Abhängigkeit vom Böschungswinkel des Erdreiches (4) angewandt werden kann, welches die Vorrichtung (1) tragen soll.

6. Vorrichtung nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die Enden der Schlitze (2) des Gewebes (1) mit kurvenförmigen Teilen ausgestattet sind, um Bruchbeanspruchungen zu widerstehen, wenn das Gewebe (1) quer zu den Schlitzen gestreckt wird.

7. Vorrichtung nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass das Gewebe mit einem geeigneten gewebten oder gestrickten Tuch zur weiteren Verstärkung der Endteile der Schlitze (2) beschichtet ist.

8. Vorrichtung nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass das Gewebe (1) aus Kunststoff hergestellt ist, beispielsweise aus Polyäthylen.

9. Verfahren zum Stabilisieren von Schüttgütern, insbesondere Erdreich, durch Verwendung eines verhältnismässig dünnen, hauptsächlich flachen Gewebes (1), vorzugsweise aus flexiblem Material, das in einer ersten Richtung mit einer Reihe von hintereinander angebrachten Schlitzen (2, 2a, 2b) versehen ist, wobei das Gewebe in passenden Längen über einen ebenen oder ein Gefälle aufweisenden Boden (4) ausgebreitet wird, dessen Erdmassen zu stabilisieren sind, dadurch gekennzeichnet, dass ein Gewebe (1) verwendet wird, das im Rahmen seiner Herstellung mit Ausbauchungen oder ähnlichen Mltteln (11) versehen ist, die eine vorgegebene Wellung von Streifen (3a, 3b, 3c) sicherstellen, wenn das Gewebe (1) in einer zweiten Richtung (3a, 3b, 3c) gestreckt wird, dass das Gewebe nach dem Ausbreiten auf der Erde (4) an seinem einen sich in Längsrichtung erstreckenden Ende im Boden (4) durch geeignete Befestigungsmittel (12) verankert wird, und dass das Gewebe (1) danach in der zweiten Richtung zur Bildung von entgegengesetzt gewellten Streifen (3a, 3b, 3c) gestreckt wird, die ihrerseits Seite an Seite liegende Zellen oder Taschen (8) bilden, die mit der durch die Vorrichtung (1) zu stabilisierenden Erde gefüllt werden können.

10. Verfahren nach Anspruch 9, dadurch gekennzeichnet, dass das Gewebe (1) nach dem Strecken seine unteren Kantenteile (1) der individuell gewellten Streifen (3a, 3b, 3c) in das Erdreich (4) eingepresst bekommt, um die Vorrichtung (1) im Erdboden (4) zu verankern.

11. Verfahren nach Anspruch 9 oder 10, dadurch gekennzeichnet, dass das Gewebe (1) am Einsatzort in der zweiten Richtung zwecks vollständiger, nicht permanenter Verformung zu den genannten Zellen oder Taschen (8) gestreckt wird, sowie dass die Deformation durch Einfüllen von Erdreich (9) in die Zellen oder Taschen (8) beibehalten wird.

12. Verfahren nach Anspruch 9-11, dadurch gekennzeichnet, dass das Gewebe (1) in geeigneter Länge am einen Gestell entlang einer seiner Endkanten befestigt wird, sowie dass das Gewebe (1) danach in einer Richtung zur Bildung von entgegengesetzt gewellten Streifen (3a, 3b, 3c) gestreckt wird, die ihrerseits Seite an Seite sitzende Zellen oder Taschen (8) bilden, die als Schutz vor herumwirbelndem Sand, Schnee o.dgl. dienen.

13. Verwendung einer Vorrichtung nach einem der Ansprüche 1-8 als Markise, z.B. zum Schutz gegen Sonnenschein, Licht, Strahlung o.dgl.

Revendications

1. Dispositif, notamment pour la stabilisation de matériaux en vrac, comprenant une nappe (1) sensiblement plane et initialement relativement mince, de préférence en un matériau souple, qui est munie dans une première direction de rangées de fentes (2, 2a, 2b) disposées consécutivement et décalées les unes par rapport aux autres, caractérisé en ce que dans la région d'une ou plusieurs fentes (2, 2a, 2b) est prévue une saillie ou un gaufrage (11) qui, pendant l'étirage de la nappe, sert à former une ondulation sur la portion de bande correspondante, dans sa direction correcte par rapport aux autres portions de bande, de manière que la nappe (1), après son étirage, forme des bandes à ondulations opposées (3a, 3b, 3c) définissant des cellules ou poches (8) disposées côte à côte et pouvant être remplies par la terre qui est stabilisée par le dispositif (1).

2. Dispositif sleon la revendication 1, caractérisé en ce que la nappe (1) dispose d'une "mémoire thermique" ou d'un étirage transversal de départ qui est réalisé pendant la production d'une nappe en matière plastique, et qui intitie la direction dans laquelle les bandes doivent être ondulées pendant l'étirage final sur le site.

3. Dispositif selon la revendication 1 ou 2, caractérisé en ce que la "mémoire thermique" ou l'étirage initial peut être réalisé dans la région des fentes, par exemple au moyen de rouleaux combinés de formation de fentes et de compression.

4. Dispositif selon l'une quelconque des revendications 1 à 3, caractérisé en ce que les bandes à ondulations opposées (3a, 3b, 3c) qui sont formées par l'étirage de la nappe (1) comprennent des portions de bord ondulées (1) qui peuvent être facilement enfoncées dans le sol (4) et assurer ainsi l'ancrage du dispositif (1) sur le site.

5. Dispositif selon l'une quelconque des revendications 1 à 4, caractérisé en ce que des degrés divers d'étirage de la nappe (1) permettent d'obtenir des angles mutuels variés entre les portions de paroi des bandes à ondulations opposées (3a, 3b, 3c), de manière à pouvoir utiliser des degrés d'étirage divers en fonction de l'angle de pente du sol (4) qui doit supporter le dispositif (1).

6. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce qu'aux extrémités des fentes (2) de la nappe (1) sont prévues des portions incurvées pour résister à une rupture quand la nappe (1) est étirée transversalement par rapport aux fentes.

7. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que la nappe est stratifiée avec un tissu tissé ou tricoté approprié en vue d'un refort supplémentaire des portions d'extrémité des fentes (2).

8. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que la nappe (1) est fabriquée en matière plastique, par exemple en polyéthylène.

9. Procédé pour stabiliser un matériau en vrac, notamment des masses de terre, comprenant l'utilisation d'une nappe (1) sensiblement plane et relativement mince, de préférence en une matière souple, qui est munie dans une première direction de rangées de fentes (2, 2a, 2b) disposées consécutivement, la nappe étant étalée selon des longueurs appropriées sur un sol plat ou en pente (4) dont la terre doit être stabilisée, caractérisé en ce qu'on utilise une nappe (1) qui, pendant sa fabrication, est munie de saillies ou moyens analogues (11) assurant la formation d'une ondulation prédéterminée de bandes (3a, 3b, 3c) quand ladite nappe (1) est étirée dans une seconde direction (3a, 3b, 3c), en ce que la nappe, après avoir été étalée sur le sol (4) est fixée sur l'un de ses bords s'étendant longitudinalement sur le sol (4) par des moyens de fixation appropriés (12), en ce que la nappe (1) est ensuite étirée dans la seconde direction pour la formation de bandes à ondulations opposées (3a, 3b, 3c) qui définissent de leur côté des cellules ou poches (8) disposées côte à côte et pouvant être remplies de la terre qui est stabilisée par le dispositif (1).

10. Procédé selon la revendication 9, caractérisé en ce que lorsque la nappe (1) a été étirée, les portions de bord inférieures (1) des bandes ondulées individuelles (3a, 3b, 3c) sont enfoncées dans le sol (4) pour ancrer le dispositif (1) dans le sol (4).

11. Procédé selon la revendication 9 ou 10, caractérisé en ce que la nappe (1) est étirée sur le site de son utilisation dans la seconde direction en vue d'une déformation non totalement permanente pour définir lesdites cellules ou poches (8), la déformation étant maintenue grâce à la terre (9) remplissant lesdites cellules ou poches (8).

12. Procédé selon les revendications 9 à 11, caractérisé en ce que la nappe (1) est fixée sur une longueur appropriée à un longeron le long de l'un de ses bords d'extrémité, et en ce que la nappe (1) est ensuite étirée dans une direction permettant la formation de bandes à ondulations opposées (3a, 3b, 3c) qui, de leur côté, définissent des cellules ou poches (8) disposées côte à côte et servant de protection contre du sable, de la neige ou analogues projetés en tourbillons.

13. Utilisation d'un dispositif selon l'une quelconque des revendications 1 à 8 en tant que bâche, par exemple pour la protection contre le soleil, la lumière, des radiations, etc.

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