WO2018231050A1

WO2018231050A1 - Block mattress

Info

Publication number: WO2018231050A1
Application number: PCT/NL2018/050373
Authority: WO
Inventors: Albert Bruins Slot
Original assignee: Abs Infradvies Bv
Priority date: 2017-06-14
Filing date: 2018-06-07
Publication date: 2018-12-20
Also published as: EP3638474A1; NL2021078B1

Abstract

Method for manufacturing an assembly of a cloth and at least one concrete element attached thereto, including providing a cloth which on a loop side is provided with loops that stand upright from the cloth, and providing at least one mold for the at least one concrete element, wherein the mold forms at least one cavity and is open on a fill side, comprising the following steps: A - positioning the at least one mold with its fill side facing upwards, B - filling the cavity of the at least one mold from above with mixed concrete, passing through the fill side, C - vibrating the at least one mold for compacting the mixed concrete, D - placing the cloth with the loop side against the mixed concrete in the fill sides, E - allowing the loops to penetrate the mixed concrete, F - placing a plate on the cloth, G - turning the assembly of plate and at least one mold around, while clamping the cloth in between them, H - if necessary, allowing the mixed concrete to set, at least until the at least one formed concrete element is shape-stable per se under the influence of gravity, I - releasing the at least one mold from the assembly of cloth having the at least one concrete element attached thereto.

Description

Block mattress

BACKGROUND OF THE INVENTION

The invention relates to a method for manufacturing a block mattress. The invention further relates to a block mattress.

Block mattresses, constituting of a cloth, such as a geotextile, and concrete blocks attached thereto, are used for covering slopes of dikes and banks.

Block mattresses are known in which prefab concrete blocks are being secured to a cloth using pins. This is a laborious process. During use, under the influence of shearing forces that arise, the pins may damage the cloth. It may furthermore happen that pins get detached when handling the mattress, in particular in case of vertically suspended transport.

Another known type of block mattress comprises a cloth provided with loops and prefab concrete blocks, wherein the concrete blocks are being positioned on the loop side of the cloth and subsequently are being attached to the cloth by means of a supplied adhesive. This manufacturing method requires a lot of effort and care.

Another known type of block mattress having a cloth provided with loops, is manufactured by positioning a pressure mold on the loop side of the cloth placed on a basis and filling the pressure mold with concrete, followed by pressing down the concrete. High forces arise in the course of all this, which form a restriction in the freedom of design for the mold or which entail high costs for the mold due to the requirements in terms of strength on the mold.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a simple method for making a block mattress. It is an object of the invention to provide a reliable method for making a block mattress.

It is an object of the invention to provide a method for making a block mattress of relatively large dimensions, without the use of added adhesive or added fasteners for the blocks.

It is an object of the invention to provide a method for making a block mattress having reliable cloth-block connections.

It is an object of the invention to provide a block mattress of relatively large dimensions, without the use of added adhesive or added fasteners.

It is an object of the invention to provide a block mattress having reliable cloth-block connections.

According to one aspect the invention provides a method for manufacturing an assembly of a cloth and at least one concrete element attached thereto, including providing a cloth which on a loop side is provided with loops that stand upright from the cloth, in particular resilient loops, and providing at least one mold for the at least one concrete element, wherein the mold forms at least one cavity and is open on a fill side, comprising the following consecutive steps:

A - positioning the mold with its fill side facing upwards

B - filling the cavity of the at least one mold from above with mixed concrete, passing through the fill side,

C - vibrating the at least one mold for compacting the mixed concrete, if necessary while replenishing the mixed concrete

D - placing the cloth with the loop side against the mixed concrete in the fill side,

E - allowing the loops to penetrate the mixed concrete,

F - placing a plate on the cloth,

G - turning the assembly of plate and at least one mold around, while clamping the cloth in between them,

H - if necessary, allowing the mixed concrete to set, at least until the at least one formed concrete element is shape-stable per se under the influence of gravity,

I - releasing the at least one mold from the assembly of cloth including concrete element attached thereto.

No high (pressure) forces arise when forming the at least one concrete element. This results in a high degree of freedom in design and in the choice of dimensions of the concrete element and of the cloth. When placing the cloth with the loop side facing downwards, the loops that are at right angles to the cloth are given the opportunity to penetrate into the exposed concrete surface. The subsequent turning around of the assembly of concrete-filled mold including cloth and plate may enhance the degree of penetration of the loops into the concrete.

The loops penetrating into the concrete may furthermore be enhanced if immediately prior to, during or just after step D, the viscosity of the mixed concrete present at least in the open fill side, is reduced. This may take place at/in the upper side of the mixed concrete, such as by adding water, and/or by an additional vibrating of the at least one mold.

In a further development the viscosity of the mixed concrete present at least in the fill sides - currently facing down - can be reduced between step G and step H, in particular by subjecting the mixed concrete to a vibration.

Filling the at least one mold from the side that will later on form the bottom side of the concrete element, offers the opportunity of designing the concrete element tapered in part or in whole, converging in a direction away from the cloth, with a tapering exceeding a tapering required to enable releasing a concrete body from a mold. In that way, the at least one mold may have a circumferential wall which at least in a part of the circumference tapers in a direction away from the cloth, at an angle exceeding 1 degree, preferably exceeding 2 degrees, for instance 5 degrees. The tapered shape may be advantageous when handling a manufactured block mattress as the blocks situated adjacent to each other less readily constitute a restriction due to mutual contact in situations in which the block mattress is bent concave, such as when the block mattress is hoisted on two sides or is transferred from a lying position into a one-sided, suspended, vertical position.

In case there is question of several concrete elements, such as blocks of a block mattress, there may be question of one mold having as many cavities as there are blocks to be formed. Alternatively, a mold may be provided for each concrete block, which molds preferably are attached to each other and form a unit that can be handled as one unity.

The used cloth can be a geotextile. The loops in the geotextile used can be tufted. In particular, the loops can be positioned in rows and per row can be part of the same length or strip of loop material. The loop rows can be mutually spaced apart from one another at a distance that exceeds the loop height. In that way the accessibility of the loops for the concrete can be enhanced, and as a result the connection to the at least one concrete element.

The loop rows can at least be slightly zigzagging. The zigzagging loop rows may each have a notional center line, wherein in the zigzagging loop rows one or more loops are situated on the one side of the center line and one or more loops are situated on the other side of the center line. The center line may coincide with a warp thread or weft thread of a geotextile fabric. In that way, it can be effected that the loops within a loop row engage onto the geotextile fabric on both sides of the fabric thread that is parallel to the loop row, which may enhance the stability and strength of the connection and the geotextile. Furthermore, the accessibility of the loops for the concrete can be enhanced, and as a result the connection to the at least one concrete element.

The loops can each be composed of a number of parallel threads, wherein the threads in the loops can be moveable with respect to each other, in the condition of the cloth prior to being placed in step D. Alternatively, the threads can be twisted into each other.

The loops may have a high resilience and tend to stand upright from the cloth.

In one embodiment the cloth at at least one edge is turned onto itself with an edge section, wherein the loops extend through a connecting portion of the turned edge section. The loops may then have been arranged after turning, so that a connection is immediately being formed between the turned edge section and the remainder of the cloth when the loops are tufted. Making that connection is facilitated when the direction of the loop rows corresponds with the longitudinal direction of the turned edge section.

The turned edge section can form an edge tube, in which a tool may extend with which the mattress provided with the at least one concrete element can be held while being moved, in particular during placing it in the work. The cloth may be provided with said turned edge section at two opposite edges.

The turned edge section with the tube may project from the at least one mold. In step D, the cloth can be placed such that the connecting portion of the turned edge section extends over the fill side of the at least one mold. As a result, the concrete also contributes to securing the turned edge section.

According to a further aspect the invention provides a block mattress having a cloth which on one side is provided with loops and concrete blocks attached thereto, in particular as a result of the method according to the invention. In particular the loops extend into the concrete standing upright from the cloth situated below the blocks.

The aspects and measures described in this description and the claims of the application and/or shown in the drawings of this application may where possible also be used individually. Said individual aspects may be the subject of divisional patent applications relating thereto. This particularly applies to the measures and aspects that are described per se in the sub claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be elucidated on the basis of an exemplary embodiment shown in the attached drawings, in which:

Figures 1A-C show a bottom view of an example of a mold for a concrete block, a side view of it and a bottom view of a group of such molds, respectively, for an exemplary embodiment of a block mattress according to the invention;

Figures 2A-F schematically show a number of steps in making a cloth for the example of a block mattress according to the invention, as well as a few details thereof;

Figures 3A-F show a few consecutive steps in the manufacturing of a block mattress according to the invention; and

Figure 4 shows an isometric view of a block mattress according to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

The mold 2 in figures 1 A and 1 B has a mold cavity 3 that is bounded by an upper wall 4 and a circumferential wall 5, that tapers at an angle a of for instance 5 degrees. The mold 2 has an open fill side 6. The dimensions L1 and B1 may for instance be 40 cm, the height H1 may be 9 cm.

Molds 2 have been joined into a group 1 , figure 1 C, in an assembly of three molds by ten molds (in figure 1A only seven of the ten rows are shown). The molds 2 can then be attached to a base plate 200 as a rigid unity, so that the group 1 can be handled as one unity. It is also possible that the molds 2 are rigidly connected one to the other by means of direct connections. The length L2 of the group 1 can then be 4 m and the width B2 can be 1 .2 m.

The cloth 10 depicted in cross-section in figure 2A, is a geotextile of polypropene threads. The woven cloth 10 has a largest length in a direction transverse to the plane of the drawing. At the longitudinal edges, edge sections have been turned (figure 2B) into turned sections 1 1 a,b while forming longitudinal cavities 13a,b. They are situated on the cloth 10 with connecting portions 12a,b. In that condition, the cloth 10 is provided with loops 20 by tufting, from the side where the turned sections are situated. The loops are arranged according to loop rows 21 , each loop row of a same elongated starting material of which the loops are consecutively tufted. Loop rows 21 are also tufted at the location of the connecting portions 12a,b, see figures 2C (by way of illustration having loops that are twisted a quarter of a turn) and 2D.

As depicted in figures 2E and 2F, the loop material consists of several (for instance ten) threads 20', which within each loop can stand slightly apart. The loops are resilient and tend to the upright position, like in figure 2E. In figure 2F it is furthermore schematically shown that within a loop row 21 the loops can be situated on either side, offset per number (in this case per pair), with respect to a cloth thread S, so that the loop row has a kind of zigzag shape.

Example: the loop height h may be 1 cm, the distance between the loop rows 21 can be 3 cm, in a loop row 21 there can be three loops within

2 cm of loop row length. The cloth 10 may have a thickness of 1 mm. The width of the turned section 1 1 a,b can be 25 cm (cavity 13a,b) + 10 cm

(connecting portion 12a,b).

Once the cloth has been manufactured like that, it can be cut transverse to the turned edge sections into cloths 10 having a width B3 of 1 .2 m in this example. The Length L3 is 4 m + the cavities 13a,b = 4.5 m.

For manufacturing a block mattress using the group of molds 1 and the cloth 10, first the group of molds 1 is placed on a carrier 100, with the fill sides 6 facing upwards, see figure 3A. The mixed concrete can then be poured into the cavities 3, from above (direction A). Once the mold cavities

3 have been filled, the group 1 can be brought into vibration (B' and B", figure 3B) to allow air to escape from the mixed concrete. If necessary the mixed concrete can be replenished.

After vibrating, the cloth 10 is placed (direction C) on the fill side 6, with the loops 20 facing downwards, figure 3C. The loops 20 can then penetrate the mixed concrete and are able to yield when a gravel stone is encountered. If so desired, after the cloth has been placed, the assembly thus obtained can be subjected to a vibration process to reduce the viscosity of the mixed concrete.

Subsequently, a rigid plate 40 is placed against the top side of the cloth 10 and clamped against it, figure 3D, wherein the cloth 10 with the loops is pressed into the mixed concrete. The unit of plate 40, filled group of molds 1 and cloth 10 is then turned around (by a turning device that is not shown), direction E, see figure 3E. In this example, the mixed concrete used has a low water-cement ratio, for instance of 0.42, so that it can be sufficiently dry/rigid for retaining its given shape when free from the mold rather quickly, so that quite soon the group of molds 1 can be lifted for diseasing, direction F, figure 3F. The block mattress 50 thus obtained rests on the plate 40, which will then further serve as tray board, as is usual.

Once the concrete has set sufficiently and the concrete has acquired the required strength, the block mattress 50 is ready for use, figure 4. Due to the loops 20 situated in the loop rows 21 , which loops may extend for a considerable part of their height into the concrete, the blocks 51 have been secured to the cloth. The loops 20 within a loop row 21 are connected to each other by the loop material, as a result of which the resistance against lifting can be high. The loops 20 may with a (small) part extend between the bottom side of the concrete blocks 51 and the cloth 10, so that there is some freedom of movement between the cloth 10 and the concrete blocks 51 (in the order of one or a few mm), which may enhance the redistribution of forces during handling and use, and for dispersing water.

The blocks 51 situated against the turned section 1 1 a,b cooperate in maintaining the turned sections 1 1 a,b.

The invention is/inventions are not at all limited to the embodiments discussed in the description and shown in the drawings. The above description is included to illustrate the operation of preferred embodiments of the invention and not to limit the scope of the invention. Starting from the above explanation many variations that fall within the spirit and scope of the present invention will be evident to an expert. Variations of the parts described in the description and shown in the drawings are possible. They can be used individually in other embodiments of the invention(s). Parts of the various examples given can be combined together.

Claims

1. Method for manufacturing an assembly of a cloth and at least one concrete element attached thereto, including providing a cloth which on a loop side is provided with loops that stand upright from the cloth and providing at least one mold for the at least one concrete element, wherein the mold forms at least one cavity and is open on a fill side, comprising the following steps:

A - positioning the at least one mold with its fill side facing upwards,

C - vibrating the at least one mold for compacting the mixed concrete,

D - placing the cloth with the loop side against the mixed concrete in the fill sides,

E - allowing the loops to penetrate the mixed concrete,

F - placing a plate on the cloth,

I - releasing the at least one mold from the assembly of cloth including the at least one concrete element attached thereto.

2. Method according to claim 1 , wherein immediately prior to, during or just after step D, the viscosity of the mixed concrete present at least in the open fill side, is being reduced.

3. Method according to claim 2, wherein the viscosity is being reduced by adding water.

4. Method according to claim 2 or 3, wherein the viscosity is being reduced by an additional vibrating of the at least one mold.

5. Method according to claim 4, wherein the additional vibrating is being carried out immediately subsequent to step D.

6. Method according to any one of the preceding claims, wherein between step G and step H the viscosity of the mixed concrete present at least in the fill side - currently facing down - is being reduced.

7. Method according to claim 6, wherein between step G and step H the viscosity of the mixed concrete present at least in the fill side - currently facing down - is being reduced by subjecting the mixed concrete to a vibration.

8. Method according to any one of the preceding claims, wherein the at least one mold has a circumferential wall which at least in a part of the circumference tapers in a direction away from the cloth, at an angle exceeding 1 degree, preferably exceeding 2 degrees.

9. Method according to claim 8, wherein the circumferential wall shows said tapering in at least almost the entire circumference.

10. Method according to any one of the preceding claims, wherein several molds, each forming a concrete element, are attached to each other and form a unit that can be handled as one unity.

1 1. Method according to any one of the preceding claims, wherein the used cloth is provided with resilient loops.

12. Method according to any one of the preceding claims, wherein the used cloth is a geotextile.

13. Method according to claims 1 1 and 12, wherein the loops in the used geotextile are tufted.

14. Method according to claim 13, wherein the loops are positioned in rows and per row are part of the same strip of loop material.

15. Method according to claim 14, wherein the loop rows are mutually spaced apart from one another at a distance that exceeds the loop height.

16. Method according to claim 14 or 15, wherein the loop rows are zigzagging.

17. Method according to claim 16, wherein the zigzagging loop rows have loops that are positioned on the one side of a fabric thread of the geotextile and have loops that are positioned on the other side of said fabric thread, in particular according to a regular pattern.

18. Method according to any one of the preceding claims, wherein the loops are each composed of a number of parallel threads, wherein the threads in the loops preferably are movable with respect to each other, in the condition of the cloth prior to being placed in step D.

19. Method according to any one of the preceding claims, wherein the cloth at at least one edge is turned onto itself with an edge section, wherein the loops extend through a connecting portion of the turned edge section.

20. Method according to claim 19, when depending on any one of the claims 14-18, wherein the direction of the loop rows corresponds with the longitudinal direction of the turned edge section.

21. Method according to claim 19 or 20, wherein the turned edge section is shaped into an edge tube.

22. Method according to claim 21 , wherein the turned edge section with the tube projects from the at least one mold, in particular from a group of molds.

23. Method according to claim 22, wherein in step D the cloth is placed such that the connecting portion of the turned edge section extends over the fill side of the at least one mold.

24. Assembly of a cloth provided with loops on one side and concrete blocks attached thereto, in particular resulting from the method according to any one of the preceding claims.

25. Slope provided with an assembly according to claim 24.

26. Mattress of blocks provided with one or more of the characterizing measures described in the attached description and/or shown in the attached drawings.

27. Method comprising one or more of the characterizing steps described in the attached description and/or shown in the attached drawings.