When it comes time to pave the paths, most often in the suburban areas they use paving slabs. It is much more aesthetic than concrete or asphalt, and is not inferior in strength to them. The easiest way is to hire craftsmen who own styling technology, but if there is no way to pay about 10 cu per square, then you can retrain for vacation time as a skid and put it on your own. The main thing is to observe the technology, which is not so complicated, find the necessary tools and decide on the “pillow” on which you will put the finishing material. It can be created from a sand-cement mixture, gravel and concrete. Consider in what cases paving slabs are laid on a concrete base and what nuances should be taken into account during installation and operation.
The concrete base is a poured and cooled down flat area on which paving slabs will be laid. This method provides a much greater coating strength than a sand-cement cushion, so it is used in places where heavy equipment or frequent traffic will exert pressure on the tile. In addition, it is much easier to align all the tiles under one level if the bottom is not a moving mixture, but a solid base. It will not shrink during the hardening process, there will be no failures and other problems associated with poor-quality tamping. Therefore, owners who do not have construction experience, but who decide to make tracks on their own, in this way, laying will simplify the alignment of the coating in one plane.
And yet, laying paving slabs on concrete is used infrequently, because this technology has its own nuances associated with the removal of moisture from the surface of the tile. In the conventional sand-cement method, precipitation leaves through the absorbent base into the ground and does not cause any harm to the coating. If concrete is poured, then the water that seeps under the paving stones cannot go deeper, since the monolithic base simply will not let it through. As a result, it gets stuck between the base and the tile, in the inter-tile seams, and as soon as the frosts hit, it begins to expand, pushing the coating up. As a consequence of this, paving stones may swell in some places, split along the edges, etc.
Therefore, when pouring a concrete base, special attention is paid to water disposal: create rulers, point moisture receivers, lay paving stones with a slope in a certain direction, etc.
If everything is organized correctly, then the created tracks will be much more durable than on a sand-cement pillow. You can lay out the most complex fantasy patterns with perfect horizontal definition of the surface.
Site preparation for construction work
The first step is to break down the site that will be paved: they drive in pegs and put the so-called red marks. With this term, builders designate a tightly stretched thread that outlines the boundaries of the future height of your site. They take ordinary twine, tie it to the pegs at the height where the tile will end. Do not forget to make the thread slope at 5 degrees to the place of future water intakes.
Next, check how many centimeters of free space from the thread to the ground. If less than thirty - remove all unnecessary with a shovel and take them away on a wheelbarrow, so as not to interfere. Fertile soil can be poured directly into the garden or in places where flower beds are planned.
The edge of the finished earthen “trough” should immediately be strengthened with borders. Some masters put curbs after pouring concrete, but in this case it will be necessary to protect the edge of the site from crumbling soil, i.e. to put the formwork. Therefore, for inexperienced bridge builders, the first option is preferable.
If a border is used, the height of which is 50 cm, then:
- dig a trench another 30 cm inland;
- fall asleep with a layer of crushed stone (about 10 cm);
- put a cement mortar (at least 1.5 cm);
- a curb is placed on it so that the top edge after laying is 2-3 cm lower than the edge of the pavers. This is necessary so that the curb does not hold water on the site, but helps to divert it.
At a lower height of the curb, the depth of the trench is accordingly reduced.
The technological process of pouring concrete
One day after the curbs have set, concrete pouring can begin. If you create a platform on which the equipment will ride, especially large-sized, the concrete base must be reinforced. For this, fittings (no more than a dozen thick) are suitable, which are knitted with a mesh size of 15-20 cm. If the tracks are exclusively pedestrian, then it is not necessary to reinforce.
In order for moisture that has got through the paving slabs to concrete to leak further, rather than stand inside, create special drainage holes. To do this, use an asbestos pipe, cutting it into pieces, a height of 15-20 cm (the height should coincide with the height of the concrete layer, which you then fill). Pieces of asbestos are laid out throughout the territory with the expectation of one per sq.m. After pouring concrete, they are not removed. You can create holes from planks in the form of squares, but after the concrete has cooled off, the tree will have to be removed.
Now we are preparing ordinary concrete using cement grade 150-200. Fill it with a layer of 15 cm - if there is no reinforcement, 20 cm - if the reinforcement is laid. If a large area is poured, then every three meters it is necessary to create a so-called temperature seam. It is needed to prevent cracking of the base in winter. The seam is easiest to do by pressing boards into the concrete with an edge half a centimeter thick. After sticking, they are removed, and the voids are filled with an elastic filler. The top of the seam is coated with concrete to level with the rest of the surface.
After a day, the wooden formwork is taken out of the drainage holes and filled in flush with the edge of the concrete with small gravel.
Creating a sand-cement pillow
The order of work here is this:
- Sift the sand, mix with cement 6: 1 (easiest in a concrete mixer);
- We fill the site with a layer of up to 10 cm (taking into account the thickness of the paving stones), i.e. cushion thickness + tile thickness should extend beyond the red mark by about 2 cm (shrink wrap).
- We tamper with a vibrating plate or a toptuha (a log on which a wide board is nailed from below, and a handle bar is stuffed from above).
- Check the tension of the red marks so that there is a slope. By the way, remember that pegs are better to put more often, because even a very tight thread gives a sag of 1 mm per meter.
- We lay out beacons on the site (pipes with a diameter of 20 mm). They must be pressed firmly to the pillow so that from the lace to the lighthouse there remains a distance equal to the thickness of your tile + 1 cm per seal. The distance between the beacons is slightly less than the length of your rule.
- Then we take the rule and tighten, focusing on the lighthouses, the excess sand-cement cushions to get a perfectly flat surface.
- We take out the first lighthouses, where you start laying tiles (you can’t step on the pillow!), Fill the furrows with the same mixture and begin laying the tiles on a concrete base.
This is how it all looks:
Laying tricks: how to do without a vibrating plate?
If you have completed all the previous steps in good faith, then putting paving stones will be easy. Tiles are not laid end-to-end, but with seams of about 5 mm. They will not allow the tiles to crack when the coating will “walk” from temperature extremes and moisture.
Start laying from the curb. Usually they move along the marks from top to bottom, in the direction where the water will flow.
Level the surface of each tile by tapping with a mallet (rubber mallet) and checking the horizontal level. In the future, you need to press the entire surface with a vibrating plate so that the tiles sit exactly along the stretched threads, but if it is not there, then immediately use a wide trim of the board when laying. It is laid flat on several tiles and beaten with a mallet to the desired height.
Tile joints can be filled with the same mixture from which you created the pillow, or with fine sand. The first option creates a monolithic coating, which passes moisture less inside. In addition, grass and moss sprout less often in the seams. But if you call on such a tile in winter with heavy vehicles, then the seams and edges of the tile may crack, since there are no heat seams. Any material, including paving stones, expands at low temperatures. And there is no clearance for this expansion. There is strong pressure in the joints, and if at that time something heavy passes through the coating, the concrete may not withstand the load.
Seams covered with sand, perfectly preserve the integrity of the coating, but through them sediments instantly fall under the tile. So the water discharge must be performed at the highest level.
To fill the joints with a mixture or sand using a regular home broom. The composition is scattered on the surface of the coating and gently swept into the seams, and excess is removed.
The site is ready. It is advisable not to walk on it for three days, so that the pillow nourishes moisture from the earth and hardens. It is better to put a board or plywood, so as not to move the edges of the tiles under pressure from the body.