Patent Application
20080098689
The invention relates to a method for shaping concrete blocks and/or concrete slabs of various formats and sizes. A method for fabricating and/or working concrete blocks is known from European Patent 0 319 972 B1, which discloses dies having recesses or projections that are randomly distributed over the die area and form a reciprocal surface on the concrete blocks. In a subsequent operation the surfaces and, as appropriate, also the edges of the concrete blocks are cleaned of loose parts and additionally roughened or damaged. Concrete blocks or concrete slabs having a rough surface with small departures from planarity but no ribbed or broached texture are obtained by the known method. Further, a method and an apparatus for artificially aging concrete blocks are known from German Patent DE 36 21 276 A1, where cured concrete blocks or concrete slabs are worked with a chisel-like striking tool so that an irregularly worked surface is produced.
The herein disclosed method for shaping concrete blocks and slabs provides a ribbing on the surfaces of the concrete blocks or concrete slabs. The surface formed by the method renders the block or slab safe for walking and slip-resistant. By virtue of the grooves or tooth strips applied to the dies or matrices, substantially reciprocal grooves and tooth strips are applied to or impressed into the surfaces of the concrete blocks or concrete slabs. Because the walls and/or roots and/or tips of the grooves or tooth strips are fashioned as parallel to one another, oblique to one another, planar or also curved, grooves or tooth strips having various flank, root or tip shapes are produced on the concrete blocks or concrete slabs. The grooves or tooth strips extend over the entire surface of the concrete blocks or concrete slabs, preferably in a regular texture, so that broaching or ribbing, that is, a special texture, is imparted to the surface. The surfaces are blasted with liquids or solids in a subsequent step. Finish working with liquid containing predominantly water is preferably carried out before the surfaces of the concrete blocks or concrete slabs have cured. Finish working with solids takes place after curing because the loading of the surface is much more intensive, so that working before curing might cause too-severe damage to the surface. The solids are preferably steel shot, because these exhibit a smooth surface and work the concrete blocks and concrete slabs intensively but not roughly. Finish working with liquids and solids is effected with jets generated for example by nozzles. There can be a plurality of jets disposed at an angle to one another. They can be moved in nonuniform fashion relative to the concrete block surface or relative to one another. The liquids or solids can also be supplied in nonuniform fashion. Finally, the concrete blocks or concrete slabs can also be moved in irregular/nonuniform fashion during finish working. Finish working with liquids and/or solids also results in the surfaces becoming safer for walking and more slip-resistant.
According to a modified proposal of the invention, instead of working with liquids or solids, it is proposed to grind flat the surfaces of the concrete blocks or concrete slabs and thus the terminal tips of the tooth strips or highs, and indeed to such a degree that the terminal tips or highs exhibit small planar surfaces. Aside from the modified visual impression, a walking surface having an increased number of edges and drainage grooves is generated in this way. The tooth strips and grooves are an effective measure for enhancing the safety of walking, in particular in the case of a ground surface combined with a dirt-inhibiting coating. According to another proposal of the invention, instead of the grooves being impressed, they are milled into the surfaces after the pressing of the concrete blocks or concrete slabs. The surfaces are preferably ground afterward, as described above. The surfaces can also be blasted. The safety of walking and/or the slip resistance is increased in this way, in particular in combination with the application of a coating described.
In preferred embodiment of the invention the grooves or tooth strips are aligned parallel to one another. They preferably run in linear fashion and parallel to one edge of the concrete blocks or concrete slabs, both the longitudinal edge and the transverse edge being usable as starting line. The grooves or tooth strips can also run obliquely to one of the edges and rib or broach the surfaces of the concrete blocks or concrete slabs diagonally. Because the grooves or tooth strips can be applied to the dies in arbitrary fashion, arbitrary shapes or textures can also be generated on the surfaces of the concrete blocks or concrete slabs, a fish-scale pattern also being possible. The cross section of the grooves or tooth strips can exhibit arbitrary shapes as viewed in cross section. Cross sections in circular arc shape also being possible, as well as rectangular and triangular cross sections having straight or curved walls.
Exemplary embodiments of the invention are illustrated in the accompanying drawings, in which:
In
As illustrated in
The surfaces of the concrete blocks or concrete slabs can additionally be treated in the fresh or the cured condition with a finish containing, for example, acrylate, paint or the like, so that a surface is obtained that exhibits a reduction or obstruction of dirt absorption and yields more-intense color and improved color fastness as well as ease of cleaning.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2006 050754.1 | Oct 2006 | DE | national |
