Device expansion joints in the concrete floor

Expansion joint in concrete floors - an important part of the equipment.

Concrete coating at high temperature expand and shrink in cold weather.

So there is a movement, and if the fabric does not provide for registration of the joint, the concrete "crawl" and cracked.

But if you run a seam all the requirements of SNIP, we get a guide that will strain and will not let her go to the side, dropping the cracks all over the floor.

In the text we will examine types of stitches, and the nuances of their device rules.

Types of joints

floors consist of a top coat and tie - almost always made of concrete, not very strong material which does not carry the force of deformation.

Because of its impact on the concrete, it will start to crack, since it does not have space for deformation of the posts below.

And if so, then in order to prevent cracking, need shtroblenie concrete joints.

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Concrete seams are of 3 types.

Insulation:

• Paul will be independent of the load-bearing walls;
• Eliminates message deformation of the walls of the concrete screed;
• created by laying insulation to pouring concrete along the walls;
• thickness averages 10 mm;
• may be a square, a circle, a straight line;
• Screed thickens to a quarter if the seam is exposed to a constant load pressure;
• can cut around the columns of hardened concrete in the shape of a rhombus.

Shrink:

• Prevents the appearance of stresses within the tie, which arises due to the fact that the surface dries out and shrinks faster than the bottom layer;
• Creates a flat surface at the weakest point;
• performed by forming the rails until the concrete has dried completely;
• suture card is desirable to make a rectangular, elongated without the parties;
• Shrink type is created, and in the outer corners to the crack did not go out of the corners.

Structural:

• comfortable with 1.5 meters from other joints, is parallel;
• If you cut through in the area where undesirable shrink or insulating seal, place the sleepers across it;
• performed strictly in places screed compounds laid at different times (usually yesterday / today).
• ties form is accomplished by attaching "a thorn in the groove".
• Structural type works similarly to the insulation.

Rules slicing

ready to tie and finished flooring are durable and will not crack, do the cutting right.

There are a number of rules that ensure the proper establishment of the joint (see also recommendations SNIP):

1. seams are cut after the screed / screed strength after dialing (after 8-10 hours after the very filling);
2. In dry concrete joints are cut in a short time - has not yet begun to pour pouring edge;
3. Test-Stroebe 2-3 hours after the concrete has started to harden if the aggregate is constantly coming out of concrete - cutting early;
4. If the blade is cutting concrete with aggregate grains, it is time to cut;
5. Stroebe device in the floor mark the rope chalk;
6. in fresh concrete cutter cutting is performed in a dry - sawed;
7. Cutting is in the order on which lay the screed;
8. Cutting is performed to a depth of 1/3 of the thickness of the screed;
9. cutting interval is: screed thickness multiplied by 24-36.When 12-centimeter screed should be cut at a distance of 288 to 432 cm with severe shrinkage Concrete is better to cut at an interval of close to 288 cm.;
10. We can not allow the T-shaped intersection of the seams, otherwise there will be cracks.

Following these rules ensures the correct implementation of the cutting and top reliable concrete floor.

modern approach

Today, you can buy ready-made designs that only need the right moment to mount directly to the screed, instead of being cut into his own.

In stores you can purchase separately:

• Shrink and compensation strap just below the tile: movable 11 mm, technical deformation 5, 8, 10 mm of synthetic resin with an insert made of soft PVC, the deformation profile of aluminum 10, 11, 17,22, 27 mm with rubber insert - replaceable / non-replaceable;
• movable structure 5, 8, 9, 10 mm, made of aluminum, brass, PVC, synthetic rubber foam;
• False profiles separately from brass, aluminum.

on the market represented a huge variety of ready-made designs, and also a separate hardware for a particular type of cutting.

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Thus, you can perform quickly and accurately stitch from scratch, simply by inserting the desired set in mortar or supplement Stroebe, done manually by placing the appropriate profile - even sealant will not have to close up.

Sealing Sealing - a prerequisite seamless operation, it is carried out using the following materials:

1. sealing cord: cord fits into the slot of expanded polyester, which retains its elasticity at constant temperature changes;
2. Sealant: the most popular method, which is a special case of filling mastics (about it will tell separately).After drying the sealant completely covers Stroebe and thus prevents water;
3. Waterstops: a special material made of polyethylene, rubber or PVC in the form of shaped ribbons, mortgaged by pouring the screed;
4. Deformation profile: uses a special profile rubber on metal rails.Rubber does not miss the water and dirt inside Stroebe, distribute the load on the tie and give concrete crack.The profile can be overlaid or embedded.

Sealing mastic

Putty - the most popular method of termination.It can be acrylic, latex, polyurethane.

Now let us consider in detail the process of sealing with mastic:

• Cooking tools and materials: mastic, brush, small triangular trowel, deep primer, sealant gun;
• Prepare the base: it should be dry and free of mold and dust, free of any oil, grease, rust and old paint - all that may affect the apprehension of mastic.Before incorporation sealant need to blow compressed air, brushed and sandblasted, primed after the process;
• interfere with sealant: Mix paste and hardener until a homogeneous composition.Do not defeat the recommended ratio!You can slightly improve the fluidity, adding 1 kg of the finished composition is about 10-12 diners gasoline spoonfuls (about 50 grams);
• Apply sealant: fill composition into the gun, after applied uniformly over the entire length, trowel leveled flush with the floor.After 40 minutes, put on a very thin layer of cement Stroebe and 1 week maximum sealant sets.

Technical requirements SNIP SNIP

requirements regarding the arrangement of the expansion joint as follows:

• in the underlying layer are expansion joints, which are located perpendicular to each other in increments of 6-12 meters;
• seam depth can not be less than 4 cm and less than 1/3 the thickness of the underlying layer;
• Stitches in the field, coinciding with the joints of the building, carried out in the entire thickness of the underlying layer;
• If the room will be subject to sudden temperature jumps, the screed settles expansion joint, which coincides with the axis of the columns, joints overlapping slabs and joints in the underlying layer;
• Stroebe device is performed via the tie cutter propyl 2 days after curing;
• When the device before the joint can be concrete masonry supply rails with a release composition, which will be removed after;
• floors in a thickness of 5 cm are provided longitudinal and transverse seams, at step 3 to 6 meters;
• After drying concrete executed jointing laying in milled groove of a special cord, and filled with sealant.

SNIP requirements partially overlap with the general rules of creating concrete joints, indicating a specialization of the work itself by cutting the seam, which does not tolerate the process "liberty."

Conclusion

seams in concrete floors - a forced necessity, dictated by the realities and SNIP rules for creating concrete structures.

in concrete floors is constantly invisible eye movement - expansion and contraction, which in the absence of space in the concrete surfaces are fraught with their slow but sure destruction.

If you think that this practice is found only in the floor, then pay attention to a lot of jumpers, that you feel when you move across the bridge.

seam in the design - it is a guarantee of its safety, and sometimes your safety.