Good afternoon, dear guests and subscribers of the "Build for Myself" channel!
If the blind area has already been made, the door to the backyard has been cut open, or you still don’t want to bother with land work, since the spouse is around has already landscaped the courtyard, that is, a very worthy version of the porch without any foundation and such a structure will last no less than itself house.
The design of such a porch is called - cantilever porch.
Construction term console denotes a special type of support in the form of a beam, protruding beyond the plane of the main wall and performing a supporting function. You can draw a certain parallel with the balcony - after all, there is no foundation for balconies, the balcony works like a console.
So it is for a concrete porch. It is not at all necessary for him to make a foundation, but it is enough to calculate a reinforcing cantilever frame in which the reinforcement will work both in tension and in shear.
Construction details
Immediately before the construction of the porch steps, a supporting cantilever frame is made with anchoring to the existing foundation. The figure below shows a top view of the foundation of the house and the cantilever frame built into it:
Anchoring is performed by the following method: a hole of 3 reinforcement diameters is drilled. Further, in the upper zone - in the tension zone - the hole depth is 30 reinforcement diameters, in the lower zone - in the compression zone - 15 reinforcement diameters.
After that, the hole is blown out and spilled with water to ensure the best adhesion to the anchoring mixture.
Then, a special anchoring agent or a mortar based on HZ self-expanding cement is injected into the hole, which wedges the reinforcement bar in the foundation (I have an article on self-expanding cement on the channel and is available at link: Cement HZ. How to make water hardened concrete?).
After anchoring the main longitudinal rods, the rest of the cantilever frame is constructed and poured into the formwork with concrete. Further, we wait for a certain period of hardening of the mixture and the frame can be loaded with concrete steps.
This design is no different from a porch on a foundation outwardly, thermal breaks are also formed between the house and the porch, it can also be tiled with tiles and other materials.
Such a porch will not sink anywhere and will not leave the foundation.
The cantilever frame freely copes with its task and holds the entire load, the main thing is to correctly calculate the reinforcement and cross-section of the beam, which is possible inexpensive to do by contacting any design bureau, since there is no universal option, everyone has different conditions and their own individual sizes!
This option is not "beaten" and you can think about it!
I hope that the article was useful and interesting for you! Thanks!
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