How to calculate the reinforcement for strip foundation - practical tips and rules

Strip foundation is most common in self-construction of various buildings.However, pouring into the mold of a concrete solution has not done.In order to strengthen the foundation of the overwhelming number of cases made it reinforcement, which greatly enhances the design and increases its load-bearing capacity.

In practice, everything for such a "wire" frame used metal bars (you can use the latest composite reinforcement).It can be smooth or ribbed, have a different diameter.But in the process of preparation for the work necessary to make the calculation of its required amount.After all, if it will be much more, which then put the excess?And if not enough, then this delay, a simple loss of time.

What to consider when calculating

1. Any metal exposed to corrosion.Consequently, reliability of design in which it was used, with its direct contact with water is significantly reduced.During installation, as well as further exploitation concrete partially begins to crumble.Plus, it with a different degree of intensity (depending on the brand, the presence or absence of various additives, waterproofing quality) gradually absorbed moisture.To protect it from the reinforcement frame is mounted so that all of its parts (bars) defended by pouring on the surface of approximately 50 mm.Moreover, on either side - on the sides, top, bottom.
2. vertical load (and transverse) of the frame (bars) is lower than the longitudinal.Therefore savings can be used to produce smaller diameter.Usually the monolith ribbon take private buildings rod 10 or 12 mm (longitudinal stacking) and 6 mm or 8 - vertical and transverse.
3. If the tape has a different width (for example, on the perimeter and inside the building, under the bearing walls), the calculation is made separately for each part.Compound
4. longitudinal members made with mutual overlap -. Approximately 50 cm Consequently, the length of each successive bar "reduced" to this value.
5. When pouring concrete frame "bursting" under the weight of the solution, especially if used with large aggregate fractions.Therefore, to further strengthen the construction of the same rod clamps are placed around the perimeter (in the form of the letter "P") to "contracts" sidewalls "lattice."
6. Number of rows horizontally and vertically depending on the tape parameter - the width and depth of bookmarks (height).To not do calculations using formulas (as they are on some sites), in which not everyone will understand, use the approximate data.For smaller private buildings that is enough.

distance between the rods in the horizontal plane is selected such that between them was not more than 25 - 30 cm. As a rule, they are placed on 4 pieces in a row.Between the vertical elements (and lateral) - from 30 to 60 cm across the tape.

How to make a calculation

makes no sense to give exact figures, because all the foundations are of different sizes.Therefore, we present only the algorithm itself by arbitrary data.Substitute the true value of their work will not make for a particular design.

• measured belt length - L. Along it will be laid in the same row, for example, 4 bar.Suppose such series, in accordance with the depth of the fill will be 3. Therefore, the total length of the rod = L x 4 x 3.
• Seats longitudinal elements compounds 24. We know that each of them "reduce" bar on the overlap length.Consequently, it turns out: 50 cm x 24 cm = 120 = 12m.
• along the entire length to be stacked staples, transverse and vertical rods.
• total length of the material is obtained:

(L x 4 x 3) + + 12 m (length of crosspieces, multiplied by their number) + (length x vertical bars on the amount) + (length x the number of brackets).

But if the whole structure is assembled from material of the same section.In the case of rods with different diameters are counted for each of them separately.The whole process of reinforcement is described in detail in this article.

the presence of internal load-bearing walls for their calculation base are conducted in the same manner.

few tips

• ribbed bars (as opposed to smooth) more reliably "engaged" with a concrete solution.
• necessary to choose rods of such a length that, when the longitudinal installation as small as possible joints.
• compounds of the corners of the tape are not allowed.Only - bending rods.
• material for reinforcement is necessary to take a little more than required, since rods segments may be needed for other purposes.For example, set the mortgages at facing the walls of aerated concrete masonry.There are many options, so you need to take into account all the nuances of construction, not to go on for several times the purchase.