Multi-layer concrete block for a paving, as well as paving and method for producing a concrete block

Abstract

The invention relates to a concrete block in the form of a planar element that can be laid in combination in order to create a paving. The concrete block has at least one multi-layer concrete block body having at least one concrete-block lower face suitable for being laid on a foundation layer of an underlying surface, and a concrete-block upper face opposite thereto. The multi-layer concrete block body has at least one first concrete-block layer disposed on the concrete-block upper face and in the form of a face concrete layer, at least one second concrete-block layer in the form of a core concrete layer, as well as a third concrete-block layer. The second concrete-block layers is disposed between the first and the third concrete-block layer. The third concrete-block layer has an increased tensile strength.

Claims

1. A concrete block, in the form of a planar element that can be laid in bond for creating a surface covering, comprising at least one multi-layer concrete block body with at least one concrete-block lower face suitable for being laid on a foundation layer of an underlying surface and a concrete-block upper face opposite thereto, wherein the multi-layer concrete block body comprises at least one first concrete-block layer disposed on the concrete-block upper face and designed as a face concrete layer, as well as at least one second concrete-block layer formed as a core concrete layer, wherein the multi-layer concrete block body also comprises a third concrete-block layer and wherein the second concrete-block layer, formed as a core concrete layer, is disposed between the first and the third concrete-block layer, wherein the third concrete-block layer is formed as a high-strength concrete base layer with increased tensile strength, wherein the increased tensile strength of the third concrete-block layer is increased in comparison with the tensile strength of the second concrete-block layer by at least 10%.

2. The concrete block according to claim 1, wherein the third concrete-block layer is made of a structurally tight, high-strength concrete, wherein the high-strength concrete, comprises a cement content of more than 380 kg/m.sup.3.

3. The concrete block according to claim 1, wherein the third concrete-block layer comprises an increased bending tensile strength and/or an increased split tensile strength and the third concrete-block layer thus comprises a specified minimum tensile strength of at least 3 N/mm.sup.2.

4. The concrete block according to claim 1, wherein the third concrete-block layer further comprises an increased compressive strength.

5. The concrete block according to claim 1, wherein an increased tensile strength of the third concrete-block layer is at least 15% higher than the tensile strength of the second concrete-block layer and at least 20% higher than the tensile strength of the second concrete-block layer.

6. The concrete block according to claim 1, wherein the third concrete-block layer is made of an armored concrete or of a concrete reinforced with at least one embedded reinforcing material.

7. The concrete block according to claim 6, wherein the third concrete-block layer is made of a fiber-reinforced concrete, of steel fiber concrete.

8. The concrete block according to claim 1, wherein the third concrete-block layer comprises a layer thickness in a range of 14 mm to 20 mm.

9. The concrete block according to claim 1, wherein the second concrete-block layer, formed as a core concrete layer, is made of a core concrete with a non-fines porous core concrete and forms a porous layer with an increased porosity.

10. The concrete block according to claim 9, wherein the second concrete-block layer is permeable to water and/or designed to absorb and store water.

11. The concrete block according to claim 1, wherein the second concrete-block layer formed as a core concrete layer comprises a core-concrete-layer thickness greater than a layer thickness of the third concrete-block layer.

12. The concrete block according to claim 1, wherein the concrete block body is formed in the form of a grating slab or bar slab, in the form of a grass grating or grass bar slab.

13. The concrete block according to claim 12, wherein the concrete block body formed as a grating or bar slab comprises at least two transverse bars and at least two longitudinal bars connecting the at least two transverse bars, wherein the at least two transverse and at least two longitudinal bars are disposed and spaced from each other in such a way that at least one continuous seepage opening extending from the concrete-block upper face to the concrete-block lower face is formed between the at least two transverse and at least two longitudinal bars.

14. The concrete block according to claim 12, wherein the concrete block body comprises at least three transverse bars and at least three longitudinal bars.

15. The concrete block according to claim 12, wherein the at least two longitudinal bars comprise a longitudinal-bar surface and the at least two transverse bars comprise a transverse-bar surface, wherein a bar height (hL) of the at least two longitudinal bars is less than a bar height (hQ) of the at least two transverse bars so that the longitudinal-bar surface is set back with respect to the transverse-bar surface.

16. A surface covering comprising a plurality of multi-layer concrete blocks laid in bond on a foundation layer of an underlying surface according to claim 1, wherein each concrete block comprises at least a first, a second and a third concrete-block layer, wherein the third concrete-block layer is formed as a high-strength concrete base layer with increased tensile strength and wherein the increased tensile strength of the third concrete-block layer is increased in comparison with a tensile strength of the second concrete-block layer by at least 10%.

17. A method for producing a concrete block according to claim 1, in which, after a formwork has been provided, at least one high-strength concrete layer is introduced into the formwork in at least a first step to produce a third concrete-block layer formed as a high-strength concrete base layer, in which a core concrete layer is introduced into the formwork in at least a second step to produce a second concrete-block layer (2b) formed as a core concrete layer and in which a face concrete is introduced into the formwork in at least a third step to produce a first concrete-block layer designed as a face concrete layer, wherein the concrete material introduced is then compressed and cured.

18. The method according to claim 17, wherein the high-strength concrete and/or core concrete introduced into the formwork is pre-compressed in one or two intermediate steps prior to the application of the face concrete.

19. The method according to claim 17, wherein the high-strength concrete is introduced into the formwork as a thin layer using first means for distributing concrete, then the core concrete is charged thickly onto to the thin layer of high-strength concrete with second means for distributing concrete, and finally the face concrete is charged onto the core concrete layer as a thin layer with third means for distributing concrete.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The invention will be explained in more detail in the following based on the exemplary embodiments in connection with the drawings. The figures show:

[0042] FIG. 1 greatly simplified and roughly schematically illustrated, a perspective view of an embodiment of a concrete block according to the invention;

[0043] FIG. 2 a roughly schematic section through the concrete block of FIG. 1;

[0044] FIG. 3 a surface covering in a highly simplified sectional view,

[0045] FIG. 4 a schematic view of a section of an embodiment of the concrete block body;

[0046] FIG. 5 a section of a further embodiment of the concrete block body in a schematic lateral view;

[0047] FIG. 6 greatly simplified and roughly schematically illustrated, a top view of the concrete-block upper face of an embodiment of a concrete block according to the invention;

[0048] FIG. 7 a roughly schematic section through the concrete block of FIG. 6;

[0049] FIG. 8 greatly simplified and roughly schematically illustrated, a top view of the concrete-block upper face of an embodiment of a concrete block according to the invention;

[0050] FIG. 9 a schematic lateral view of the concrete block of FIG. 7 and

[0051] FIG. 10 a roughly schematic section through the concrete block of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION

[0052] FIG. 1 shows a perspective view of an embodiment of the concrete block 1 according to the invention in a highly simplified schematic drawing, and FIG. 2 shows a schematic section along a section plane running parallel to a middle vertical axis MHA and parallel to a longitudinal axis LA of concrete block 1.

[0053] Concrete block 1 is preferably designed in the form of a planar element that can be laid in bond to create a surface covering 10 (see FIG. 3). In the present understanding, concrete block or concrete slab are essentially structurally identical elements that can be used for creating a surface covering 10 in a manner that is known in itself. For example, the concrete block 1 can be a concrete paving block. Depending on the selected laying patterns, the concrete blocks 1 are laid in bond and flush with each other so that a preferably flat paving 10 is created.

[0054] The concrete block 1 comprises at least a multi-layered concrete block body 2 with at least one flat concrete-block lower face 2.1 and an essentially flat concrete-block upper face 2.2 opposite, which preferably forms the tread or drivable surface or also a traffic area. The precise embodiment of the lateral surface sections of concrete block 1 is not relevant for the invention, i.e., the precise cross-sectional shape of concrete block 1 can be chosen almost arbitrarily without thereby abandoning the idea of the invention.

[0055] In the present exemplary embodiment, the concrete block 1 is cuboid in shape and comprises two pairs of two concrete-block faces of the same surface and facing each other 2.3, 2.4. The concrete-block lower face 2.1 and the concrete-block upper face 2.2 run vertically or approximately perpendicular to the middle vertical axis MHA of the concrete block body 2 and concrete block 1 respectively. The concrete-block faces 2.4 extend essentially perpendicular to the longitudinal axis LA and the concrete-block faces 2.3 extend essentially parallel to the longitudinal axis LA.

[0056] The multi-layer concrete block body 2 comprises at least a first concrete-block layer 2a, which is formed as a face concrete layer and forms the concrete-block upper face 2.2, at least a second concrete-block layer 2b adjacent to the first concrete-block layer 2a in the direction of the middle vertical axis MHA and formed as a core concrete layer, and a third concrete-block layer 2c connected to the second concrete-block layer 2b in the direction of the middle vertical axis MHA, which forms the concrete-block lower face 2.1 and is intended to be supported on a foundation layer 3 of an underlying surface. The second concrete-block layer 2b, which is formed as a core concrete layer, is thus disposed between the first and third concrete-block layers 2a, 2c.

[0057] The third concrete-block layer 2c is designed as a high-strength concrete base layer and comprises an increased tensile strength, in particular, an increased bending tensile strength.

[0058] In the example shown in FIGS. 1 and 2, the third concrete-block layer 2c is made of a high-strength concrete, wherein the high-strength concrete of the third concrete-block layer 2c is a structurally dense concrete with a cement content in a range between about 350 kg/m.sup.3 and 450 kg/m.sup.3, preferably between 380 kg/m.sup.3 and 400 kg/m3. The high-strength concrete of the third concrete-block layer 2c, for example, comprises a compressive strength of at least 55 N/mm.sup.2 and a bending tensile strength of at least 5 N/mm.sup.2. The third concrete-block layer 2c is made in particular, of a high-strength concrete, as defined in accordance with the set of standards, wherein the concrete for producing the third concrete-block layer 2c is, for example, a high-strength concrete of compressive strength class C55/67.

[0059] The third concrete-block layer 2c of the concrete block 1 of the example shown comprises a layer thickness d, which lies in a range between about 16 mm and 18 mm. In the exemplary concrete block 1 shown in FIGS. 1 and 2, the first concrete-block layer 2a, which is formed as a face concrete layer, comprises a face-concrete-layer thickness dV, which can be in a range between 10 mm and 20 mm. The second concrete-block layer 2b, which is formed as a core concrete layer with its core-concrete-layer thickness dK, is the layer with the greatest layer thickness in the example concrete block 1 shown in FIGS. 1 and 2, i.e., the core concrete layer here occupies the largest proportion of the concrete block body 2, which comprises a total height H, which preferably corresponds to the sum of the layer thicknesses dV, dK, d of the first to third concrete-block layers 2a, 2b, 2c.

[0060] The second concrete-block layer 2b, which is formed as a core concrete layer, is made of a non-fines porous concrete and thus forms a water-permeable or water-absorbing layer in the concrete block body 2. The concrete composition of the non-fines porous second concrete-block layer 2b is such that the second concrete-block layer 2b is equipped with pores, in particular, in the desired or defined number of pores as well as the desired or defined average size of the pores. Rainwater that hits the concrete block 1 laid in a surface covering 10 in its state of use can be absorbed into the pores of the second concrete-block layer 2b or also run off through the pores. The second concrete-block layer 2b can also be used, in particular, for water storage.

[0061] For optimal absorption and storage of water, the core-concrete-layer thickness dK of the second concrete-block layer 2b is between 40% and 80% of the total height H of the concrete block body 2, preferably between 50% and 70% of the total height H of the concrete block body 2.

[0062] In the exemplary embodiment shown, concrete block 1 comprises so-called spacers or spacer lugs 9, which ensure uniform joints 11 (see FIG. 3) in approximately uniform width when laying concrete block 1 in bond and ensure a minimum width of joints 11.

[0063] FIG. 3 shows an example of a section through a surface covering 10 formed from the existing concrete blocks 1. The surface covering 10 comprises a plurality of multi-layer concrete blocks 1 laid in bond on a foundation layer 3 of an underlying surface. Joints 11 are formed between adjacent concrete blocks 1 of the surface covering 10, which are filled with a joint material 12 and form a seepage path for the drainage of rainwater from the surface of the surface covering 10 facing away from foundation layer 3. Foundation layer 3 is a conventional foundation layer that essentially consists of a mixture of materials with a grain size of 0.1 mm to 5 mm.

[0064] The production or manufacture of the present concrete block 1 can be carried out by means of industrial manufacturing methods, in which concrete blocks 1 are produced in a process-controlled manner, preferably in layers, i.e., a plurality of concrete blocks 1 simultaneously in one layer. First, as part of the manufacturing method, a well-known concrete formwork is provided for producing concrete blocks 1. After the formwork has been provided, at least one high-strength concrete is placed in the formwork in at least one first step to produce the third concrete-block layer 2c, which is designed as a high-strength concrete base layer. In at least a second step, a non-fines porous core concrete is also introduced into the formwork to produce the water-permeable second concrete-block layer 2b, which is formed as a core concrete layer, and in at least a third step, face concrete is introduced into the formwork to produce the first concrete-block layer 2a, which is formed as a face concrete layer. The concrete material is then compressed and cured.

[0065] FIGS. 4 and 5 show a schematic sketch of the layer structure of the concrete block body 2 on the basis of a schematic section of the concrete block body 2 of a respective embodiment of the present concrete block 1. In the example of FIG. 4, the third concrete-block layer 2c, which is formed as a high-strength concrete base layer, is made of a structure-tight, high-strength concrete, as already described above. In the concrete block body 2 of the example of FIG. 5, the third concrete-block layer 2c is additionally reinforced or armored. Here, a armor or reinforcement material is embedded in the concrete of the third concrete-block layer 2c in order to additionally increase the tensile strength, particularly the bending tensile strength. In the example shown, a fiber reinforcement or fiber armor is provided for this purpose, wherein the fibers embedded in the concrete are 13 steel fibers or steel wire fibers, for example, and the third concrete-block layer is therefore a layer made of steel fiber concrete.

[0066] With reference to FIGS. 6 to 10, further, particularly preferred embodiments of the present concrete block 1 are described, namely variants of concrete block 1, which are designed as a grating block or as a bar slab, namely as a grass grating block 4 or a grass bar slab 5. The grass grating block 4 can also be synonymously referred to as the grass grating slab 4 and the grass bar slab 5 can also be synonymously referred to as the grass grating block 5.

[0067] The concrete block body 2 of the grass grating or grass bar slab 4, 5 comprises transverse bars 6a, 6b as well as the longitudinal bars 7a, 7b connecting the transverse bars 6a, 6b, wherein the transverse and longitudinal bars 6a, 6b, 7a, 7b are disposed and spaced in such a way that one or a plurality of seepage openings 8 is/are formed between the transverse and longitudinal bars 6a, 6b, 7a, 7b. Each seepage opening 8 extends continuously from the concrete-block upper face 2.2 to the concrete-block lower face 2.1 and forms an open cavity or free space on the upper and lower sides or a break in the concrete block body 2.

[0068] The grass grating or grass bar slabs 4, 5 can also be used for creating a surface covering laid in a familiar way in bond and are used, for example, particularly for surface coverings covered with vegetation or surface coverings covered with greenery or for the purpose of surface reinforcement in green areas. The seepage openings 8, which are open upwards towards the concrete-block upper face 2.2 and also downwards towards the concrete-block lower face 2.2, are filled with soil, sand or the like when laid and serve as a planting space in which the greenery plants, such as grass for example, can grow and can even directly reach the soil below with their root system.

[0069] The concrete block body 2 of the grass grating block 4 shown in FIGS. 6 and 7, which is shown in FIG. 6 in a top view of the concrete-block upper face 2.2 and in FIG. 7 in a section along the line A-A, is essentially cuboid and comprises two outer transverse bars 6a, a middle transverse bar 6b as well as two outer longitudinal bars 7a and two middle longitudinal bars 7b. The transverse bars 6a, 6b run essentially parallel to each other and perpendicular to the longitudinal bars 7a, 7b, which in turn are disposed parallel to each other. The outer transverse and longitudinal bars 6a, 7a form the perimeter sides of the concrete block body 2, namely the concrete-block faces 2.3, 2.4 and are designed as a surrounding circumferential surface. It is to be understood that the number and arrangement of the transverse bars and longitudinal bars 6a, 7a is only exemplary and can of course deviate from the illustration of FIGS. 6 and 7 without thereby abandoning the idea of the invention.

[0070] The transverse and longitudinal bars 6a, 6b, 7a, 7b comprise the same height in the example shown in FIG. 4 so that the respective transverse-bar surfaces 6a1, 6b1 and respective longitudinal-bar surfaces 7a1, 7b1 are essentially taken up in a common plane and together form an upper, essentially flat surface of the concrete-block upper face 2.2.

[0071] The grass grating block 4 shown as an example comprises six seepage openings 8 and thus six continuous openings. As can be seen from the cross-sectional view of FIG. 7, both the transverse bars 6a, 6b and the longitudinal bars 7a, 7b are constructed in three layers and comprise the first concrete-block layer 2a, which is designed as a face concrete layer, the second concrete-block layer 2b, which is formed as a core concrete layer, and the third concrete-block layer 2c, which is designed as a high-strength concrete base layer.

[0072] FIGS. 8 to 10 show an example of a preferred variant of the present grass bar slab 5, which is shown in FIG. 8 in a top view of the concrete-block upper face 2.2, in FIG. 9 in a lateral view and in FIG. 10 in a section along the line B-B indicated in FIG. 8.

[0073] The concrete block body 2 of the example shown comprises four transverse bars 6a, 6b and three longitudinal bars 7a, 7b, wherein the three longitudinal bars 7a, 7b are essentially zigzagging and connect the four straight transverse bars 6b, 6b, in such a way that neighboring transverse bars 6a, 6b are disposed offset in their length from each other. The transverse bars 6a, with their flush ends at a first edge of concrete block 2 (in FIG. 8, right), form an outer edge defining the outer perimeter, and analogously, the transverse bars 6b, with their flush ends on an opposite edge of concrete block 2 (in FIG. 8, left), form an opposite outer edge.

[0074] It is to be understood that both the shape of the longitudinal bars 7a, 7b and also the number and arrangement of the transverse and longitudinal bars 6a, 7a are merely exemplary and may of course deviate from the illustration of FIGS. 8 to 10 without thereby abandoning the idea of invention.

[0075] In the example of FIGS. 8 to 10, the transverse bars 6a, 6b comprise a bar height hQ and the longitudinal bars 7a, 7b comprise a bar height hL, wherein the bar height hL is less than the bar height hQ. With regard to an upper surface defined by the concrete-block upper face 2.2, the respective longitudinal-bar surfaces 7a1, 7b1 are thus set back vertically downwards in relation to the transverse-bar surfaces 6a1, 6b1. As can be seen from FIG. 10, the grass bar slab 5 is also designed in three layers and includes the first, second and third concrete-block layers 2a, 2b, 2c.

[0076] In the case of the grass bar slab 5 shown as an example, the longitudinal-bar surfaces 7a1, 7b1, which are set back downwards, are covered or filled with soil and/or sand in case of application, i.e., in the installed state so that essentially only the transverse-bar surfaces 6a1, 6b1 are visible to the outside. Plant growth or greening is thus possible not only in the area of the seepage openings 8, but also in the entire area between the transverse bars 6a, 6b, i.e., over the entire area between the transverse bars 6a, 6b, which is why in these special forms of application it is also possible, for example, to use the concrete block body 2 in the area of the longitudinal bars 7a, 7b to dispense with the first concrete-block layer 2a, which is designed as a face concrete layer, as shown by way of example in FIG. 10.

[0077] In the case of concrete blocks 1, which are designed as grass grating blocks or grass bar slabs 4, 5, the third concrete-block layer 2c, which is designed as a high-strength concrete base layer, has a particularly favorable effect, since the concrete block bodies 2 of these embodiments are generally less stable in comparison with solid blocks due to the existing seepage openings 8 formed by respective openings. However, the loss of stability resulting from the perforated structure can be more than compensated for with the high-strength concrete base layer so that this results in extremely stable, particularly break-resistant grass grating blocks or grass bar slabs 4, 5. Particularly in the case of these embodiments as grating blocks or bar slabs, the fact that the concrete block bodies 2 can be manufactured at a lower height due to the high-strength concrete base layer has a particularly favorable effect.

[0078] In combination with the third concrete-block layer 2c, i.e., with the high-strength concrete base layer, in the case of the present grass grating or grass bar slabs 4, 5, the second concrete-block layer 2b, which is pervious in terms of its density and porosity, can also be adapted in an ideal, optimal way in terms of its density and porosity for a particularly effective and good water conductivity or water storage capacity, without thereby having to accept the disadvantage of low stability and fracture resistance of the concrete block 1. The lawn lattice or lawn bar slabs 4, 5 are therefore particularly well adapted to their intended use and ensure an effective, effective water supply to the greenery or growing plants. The non-fines porous second concrete-block layer 2b can thus be specially adapted to store water and later, particularly in longer dry phases, gradually release it back to the plants so that concrete blocks 1 can also make a significant contribution to the supply of the plants to survive dry periods.

REFERENCE LIST

[0079] 1 concrete block [0080] 2 concrete block body [0081] 2a first concrete-block layer [0082] 2b second concrete-block layer [0083] 2c third concrete-block layer [0084] 2.1 concrete-block lower face [0085] 2.2 concrete-block upper face [0086] 2.3, 2.4 concrete-block faces [0087] 3 foundation layer [0088] 4 grating slab [0089] 5 bar slab [0090] 6a, 6b transverse bars [0091] 6a1, 6b1 transverse-bar surface [0092] 7a, 7b longitudinal bars [0093] 7a1, 7b1 longitudinal-bar surface [0094] 8 seepage opening [0095] 9 spacer [0096] 10 surface covering [0097] 11 joints [0098] 12 joint material [0099] 13 fibers [0100] d layer thickness of the third concrete-block layer [0101] dK core-concrete-layer thickness [0102] dV face-concrete-layer thickness [0103] H total height of the concrete block [0104] hL bar height of the longitudinal bars [0105] hQ bar height of the transverse bars [0106] MHA middle vertical axis [0107] LA longitudinal axis