OBTAINED USING THE METHOD

Paving slab, paving slab production method, and paving slab obtained using the method.

The invention relates to a paving slab, a method to produce a paving slab, and a paving slab obtained using the method, applicable in production of paving slab modules including natural stone elements, in particular, used for pavement surfaces .

Paving slabs are used for building pavements, paths, alleys, terraces or driveways. The aim is to harden the surface, but the aesthetic result and appearance are also important. Therefore, pavements containing natural stone in their structure become more and more popular, characterized by uneven surface, irregular shape, which makes it look natural and unique. Laying natural stone of irregular shape on more or less hardened substrate becomes, however, burdensome and makes obtaining flat external surface of so created pavement practically impossible. Therefore, paving slabs are used that contain natural stone in their volume, joined into larger slabs with a binder. A method of production of natural stone panels made of rectangular stone blocks is known from US patent application No. 4218496. The method comprises making a grid of rectangular blocks face down on the working surface, placing a glass fiber mat on the back with concurrent application of an adhesive material that may contain stone dust filler, a resin and a setting agent, on the joints between adjacent stone blocks. After setting, the front surface of the slab is polished and covered with a protective layer. The said method relates to regular block of natural stone, prepared beforehand and cut into identical cuboids. The mat of glass fiber cannot be applied on irregular surface of natural stones often having sharp edges that might damage the mat, significantly reducing its strength properties. Furthermore, the adhesive compounds used are not sufficiently strong and using them form binding large natural stones may result in damaging whole paving slabs.

Further on, international patent application No. WO0166874 discloses stone surfacing for countertops, walls and floors and the method to produce thereof. The said method comprises arranging stone tiles having finished planar surface, a plurality of side surfaces, and an unfinished surface of the tile planar work surface in edge-to-edge contact, and applying a stone-penetrating adhesive to the unfinished surface and the side surfaces, and then adhering the unfinished surfaces to a rigid substrate and further applying a support structure fixed to the application surface. The method referred to relates to natural stones having the form of cuboids and will not be effective for natural stones with irregular, often sharp edges. Using an adhesive in the form of mastic does not guarantee bonding large stone fragments strongly enough and may cause their falling off or even fracturing the slabs. Furthermore, the rigid substrate must be fixed to the flat unfinished surface of the tiles, and fixing it to an irregular stone surface may be difficult if not impracticable. The technical problem faced by this inventions is to provide such a method of production of stone slabs containing irregular natural stones in their volume and front that ensures obtaining flat front surface, enables using irregular stones of any shape, even with sharp edges, wherein durable and strong binding even large and heavy natural stones will be possible, and the method will not use complex and costly to produce adhesive layers, and will limit the number of technological steps, positively influencing the manufacturing time and cost of a single slab. Unexpectedly, the technical problems mentioned above have been solved by the present invention .

The first object of this invention is a paving slab containing filling elements of irregular structure in its volume and on its front side, preferably natural stone elements, of flat front surface, characterized in that the filling elements are bound with concrete constituting the base of the paving slab up to h of its height, and the gaps between the filling elements are filled with grout up to the total height of the paving slab.

The second object of this invention is a method to produce paving slabs containing filling elements of irregular structure in its volume and on its front side, preferably natural stone elements, characterized in that it comprises the following steps: a) preparing of a matrix, b) covering the matrix with a non-adhesive film, c) arranging the filling elements on the matrix, leaving gaps between them, d) pouring the grout upon the arranged filling elements, filling the gaps between the elements up to height h of the matrix, e) wetting the exposed surface of the filling elements in order to improve concrete adhesion to the filling elements, f) flooding the matrix and the arranged filling elements partly grouted, with concrete up to the total height of the matrix, g) leaving the so created slab for preliminary setting, h) removing the matrix, i) leaving the slab until fully set, j) turning the slab by 180°, removing concrete flashes, and completing the grouts.

In the preferred embodiment of the invention, the non-adhesive film in step b) is a layer of material selected from a group comprising: plant or mineral oils. In another preferred embodiment of the invention, the grout in step d) is a material selected from the group comprising: rock flours (granite flour, basalt flour), polyurethane based mixture grouts .

The third object of this invention is a paving slab containing filling elements of irregular structure in its volume and on its front side, preferably natural stone elements, with flat front surface, characterized in that it has been made according to the method as defined in the second object of the invention .

The production method according to the invention enables manufacturing of paving slabs with flat front surface, containing natural stones of irregular structure and with sharp edges in its volume and on the front surface, wherein it is possible to permanently bind even large and heavy stones. The presented method is easy to implement and contains simple and relatively cheap technological steps requiring no special tools. Implementation of concrete to bind the stones determines the strength of the whole slab and reduces manufacturing cost. Exemplary embodiments of the invention have been presented in the drawings, where fig. 1 is a perspective view of the paving slab obtained with the method according to the invention, fig. 2 shows a lateral view of the paving slab from fig. 1, and fig. 3 illustrates the matrix.

Example

In the first step, the paving slab matrix was prepared, i.e. cleaned from the remains of the previous technological process. The matrix has been made of construction steel and contains 6 cells, each measuring 300x300x80, and its perspective view is presented in fig. 3. The inner surface of the matrix were covered with a thin non-adhesive film 1 of rapeseed oil. Upon so prepared matrix, natural stones 2 of irregular texture were laid face down, leaving gaps of 1 mm to 10 mm between the stones 2. Grout 3 of basalt flour was poured on stones 2 placed in the matrix and evenly distributed with compressed air in the gaps to the height ≥ 40 mm in the matrix. Having applied the grout 3, the exposed surface of natural stones 2 was wetted with water in order to remove the residues of dust after grouting and to increase concrete adhesion to natural stones 2 as well. Then, the matrix was filled with concrete 4 up to its full height. So prepared paving slab was left for preliminary setting for 24h. After the initial setting, the matrix was removed by pulling out the dividing elements and taking off the limiting elements. Further on, the paving slab was left until concrete 4 had fully set, i.e. for 72h. After full setting of concrete 4, the paving slab was turned over by 180°, concrete flashes were removed, and grouts 3 were filled as needed. So prepared slab was placed on a pallet and was ready for transportation. The slab produced with the method described above is illustrated in fig. 1. It was characterized with flat front surface. Utilizing the matrix enabled using natural stones 2 of irregular shape in the volume and on the front. Using concrete 4 as the binder, in turn, allowed using heavy stones 2 even with sharp edges without worrying about damaging the structure of the slab itself. The face of the slab consisted of stones 2 arranged face up, surrounded with grout 3, which allowed obtaining the effect of laying the stones 2 directly upon rigid substrate.