Soon to fill the foundation?
So you need to order fittings, because the foundation construct is called that reinforced concrete, where the word "iron" just means a reinforcing cage made of steel bars of the corresponding diameter.
Buying rolled metal products and relying on the conscientiousness of builders, most future homeowners do not pay attention to what exactly they are buying, thinking that fittings in Africa are also fittings!
So, steel reinforcement serves to increase the strength of the structure, as well as to resist various loads. It is made of carbon steel or alloy steel and can be made with a smooth or ribbed profile. Bars with a smooth surface belong to the class of reinforcement А-I (А240), and bars with a corrugated surface are already classified as: A-II (А300); A-III (A400, A500); A-IV (A600); A-V (A800); A-VI (A1000).
In order for the reinforcement rod to correctly perceive the load, it is very important to locate it geometrically correctly inside the reinforced concrete structure. If these are not oblique elements, then the rods in reinforced concrete structures are located strictly at angles of 90 degrees as to the walls structures, and relative to each other, forming a reinforcing mesh, at the base of which is either a rectangle, or a square.
The builders achieve the correct positioning of the reinforcement using clamps that rest against the formwork and do not allow the reinforcing bars to bend. So that the frame does not fall apart and does not deform during concrete work, the intersection of reinforcement rods are tied with knitting wire and for rigidity and stability, the joints are seized with welded connections.
So we come to the question of the type of fittings.
I have seen many times how the reinforcement cages "float" together with the concrete poured from the mixer, the vertical rods that hold the horizontal reinforcement fall to one side together with the concrete creeping along the trench and the frame loses its geometry, since the knitting wire does not withstand such a load and all the crosshairs and joints begin deform. For this, the joints of the frame must be welded. No, of course not all, but at least 20-30% to ensure the required rigidity.
If the concrete were transparent, then looking at their foundation, the owners would gasp - more than 90% of the reinforcement cages, made without welding, are located in the foundations at random!
That is why, instead of conventional fittings for example A500, I always advise taking A500C, where C is the tolerance for welding, including for electric arc welding. In addition, such reinforcement is much more ductile and stronger, and even more resistant to corrosion.
Almost everyone has heard the myth that fittings cannot be cooked, but this is just another myth. For this, such fittings are manufactured to ensure good weldability without loss of joint strength.
In view of what, in order to sleep peacefully and not regret after the construction of the foundation, it is important when buying to focus on the type of reinforcement.
The fact is that if ordinary A500 fittings are welded, the assembly loses strength and the metal becomes brittle. This is due to the fact that when exposed to high welding temperatures, the heated hardened metal is "tempered", greatly losing strength. In A500C rods, alloying additives are specially minimized in accordance with GOST 52544-2006, so that the steel has good ductility and weldability.
And that's all, I hope the article was useful to you!
Thank you for the attention!