Paving granite stone will make your yard much more attractive, and paving stone will be much easier and will hold on for a long time!
In the cities of many European countries and Canada the ornamented covering with paving stones or granite slabs of sidewalks and squares has long been an integral element of urban decoration. The use of this artistic technique in street architecture has a historically established justification: up to 40% of the time a person stays on the street looks under his feet, and the “foot architecture” can have the same aesthetic impact on a pedestrian as the view of the surrounding buildings or green zone.
If the solution is found correctly, the laid surface can form a whole with the environment. In this case, a person raising his or her head and translating his or her gaze from the bridge to the buildings or the park, gets a complex perception of this architectural ensemble. Paving granite of a paving stone is preceded by a choice of a material and drawing (scheme) of packing.
As a rule, the basic material for paving stone coverings is a stone of strong breeds: granite, gabbro, basalt, porphyry, diabase, etc. – These types of stone have a high durability, perfectly resisting intensive mechanical impact. The cost of granite and the price of paving granite stone laying pay off its durability.
Types of granite used in works on paving granite.
Paving stone from granite, used in modern urban development, can be divided into three types, depending on the nature of processing:
1) is obtained by chipping or otsetsyvatsya granite on all six faces;
2) sawing off the stone from 4 sides and scalding on two faces (front and rear) – such a granite paving stone, preserving the classic punched texture, allows you to easily carry out laying due to good geometry on the perimeter;
3) the result of sawing off the stone on all 6 faces. Being a compact element of paving, paving granite stone allows to receive a huge variety of various ornaments – from the simplest rectangular laying to circular, arched, wavy, fan-shaped, etc.
The highest aesthetic level, the art of paving granite reaches when using the smallest stones. In terms of quality of execution of granite laying can approach the artistic mosaic.
The technology of work on laying of a granite
In general, the layout includes the following operations in the order they are performed:
1. Removal of the soil layer (turf) to a depth of 150 mm.
2. Layout of the surface to be laid (longitudinal and transverse) with observance of technological slopes for water runoff.
3. The surface to be laid (longitudinal and transverse) with observance of technological slopes for water drainage rammed or vibrocompacted with the help of a vibratory plate weighing 300-600 kg (with centrifugal force about 30-50 kN).
4. Digging grooves under the side stone.
5. Trammeling the bottom of the groove.
6. Dumping on the bottom of the groove layer of sand fraction 0-4 mm thick 50 mm.
7. Laying on layers of sand of concrete cushion 50-80 mm thick.
8. Installation in a groove on the concrete cushion of a side stone.
9. Covering the earth bed with geotextiles (for weak soils).
10. Dumping of a covered surface with rubble fraction 5-20 mm in thickness of a layer of 100-200 mm (under condition of movement of motor transport); at nonpure soils, without movement of motor transport, dumping by large humidifying sand with thickness of a layer of 100-150 mm is supposed.
11. Watering of a surface of the sprinkled layer with water with the subsequent ramming.
12. Formation of the underlying base (three options):
a) To lay the granite more than 60 mm high – filling on tamped crushed stone layer of wet sand fraction 1-5 mm thick 50-80 mm with a subsequent alignment of the lath (sand must be sorted by removing iron oxides, dirt and clay);
b) for paving stones less than 60 mm high – stacking on the surface of the leveled, moistened and rolled sand layer of 0-4 mm thick reinforcement mesh 50 * 50 mm (without binder) with a dry mixture with a layer thickness of 30-40 mm (subsequent weak moistening with the help of a watering can);
c) for moderate mechanical effects – laying a bed of cement-sand mortar M150 of 20-30 mm thick directly on tamped crushed stone (without sanding).
Other recommendations for paving granite
The following base structure is recommended: a 50-100 mm thick concrete screed is laid on a leveling layer of sand or crushed stone laid on the ground, on which paving slabs are laid using the adhesive composition (in exceptional cases, the concrete layer can be reinforced with metal mesh). For coatings working in difficult conditions (heavy loads, weak soils, etc.), it is also possible to lay paving stone on cement mortar.
Selection of material is a rather simple preparatory operation for laying treated paving slabs (especially if they are modular), but it is labour-intensive for “wild stone“, which has to be selected according to its shape. And paving granite stone is no exception: although the price of a wild stone is much lower, the cost of work increases due to the time spent on selection. Preparation of the base is largely determined by the structure of the soil and the nature of the assumed loads on the coating. For paving stones designed for intensive loads (roadways, parking lots, etc.), weak soil, as well as the use of slabs of limited thickness (20-40 mm).
At first, choose the thickest granite slab of relatively correct shape and place it so that when the final laying on the base it was in the most visible place (the choice of the thickest paving stone is due to the fact that it was easier to adjust the height of the other stones with the mixture).
How to lay a paving stone
Depending on the intensity of the assumed loads and the state of the soil, produced on a sandy, crushed stone (gravel) or concrete base (in case of weak soils is recommended to pre-stack the earth bed with geotextiles to prevent deformation of the roadbed).
If the paving surface is designed for heavy traffic, it is recommended to lay paving granite stone on the concrete screed with a solution with adhesive additives. The process of paving granite is accompanied by a control of the flatness of the paved surface, carried out by means of a control strip. When the paving is completed, the seams are sealed.
When paving granite it is necessary to ensure that the front surface of all boards was at the same level with the minimum thickness of glue. A day after laying (when the glue is glued but has not yet hardened) you can lightly clean the granite with a brush and rinse it with water. The glue in the gaps is partly washed out, forming a slightly concave groove.
It is recommended to sprinkle the surface of granite paving stones and paving slabs with water for several days until the final hardening of the adhesive mixture. Paving areas adjacent to buildings should be laid in such a way that the runoff of surface water passes from the building; otherwise, drain gutters and rain gutters should be provided directly at the building itself.