Can the concrete tape be poured in stages or in layers?

Pouring large volumes of concrete in one go is not an easy task. Usually, with significant volumes, factory concrete is ordered in concrete trucks. If there are difficulties with access roads, then order a concrete pump. But you must admit that for 3-4 m3 of concrete, his order doubles the cost of the concrete itself. What if you pour it with self-weight concrete, but in parts? In what cases can this be done, and in what cases is it unacceptable?

It all depends on the object. If the object is not responsible, as, for example, in my case with a concrete tape under the fence, then, I think, this is permissible. I did so.

First, I reinforced (4 rods) and concreted a trench for a shallow tape (flush with the ground). Filled in 4-5 spans. Then he exposed the formwork for 2-3 spans above the ground (boards made of boards). Also reinforced. Used fiberglass fittings. He made self-weight concrete of the M200-250 brand.

He took off the formwork the next day, moved it further and poured it again. It turns out that the seam between the poured sections was not 100% cold (as they say). Because concrete gains most of its strength up to 14 days, then in this seam the concrete is to some extent adhered between the layers.

I also do not see anything critical that the tape itself was filled with two layers. If it is planned to leave the poured part of the concrete for more than 2 days, then it is better to reinforce this place with reinforcing rods and make the seam as horizontal as possible. Monolithic multi-storey buildings, or rather, their columns are flooded. The main thing is that the concrete parts are connected with reinforcement running perpendicular to the plane of the seam.

I will not say that everything is perfect and there is not a single crack in the tape. At 100 meters of the length of such a fill, I found cracks only in two places, which do not open further in any way. It is possible that they were formed not from the heaving of the soil, but from the temperature compression of concrete at this length, because each concrete segment is sandwiched between metal posts.

Is it possible to do this on strip foundations of houses? If this is done in layers, then it is permissible for wooden houses. Also fill the trench, and then set the formwork and continue pouring. But the layers should be solid monolithic here.

At neighbors' two sites, builders topped up (increased the height) of the strip foundation a year after pouring the first option. We decided that the tape was too low.

I am not calling for such options, since they are a compromise. Ideally, pour everything, of course, at one time. Because any seam is a water seepage gap.

I also poured tape or stiffeners over the slab foundation for my house after pouring the bulk. Thus, he increased the height of the foundation and raised the aerated concrete masonry from getting wet. I wrote about this in article.

But here is such a crushing of the stages of pouring unacceptable in beams, lintels, floor slabs. Cold seams in these can lead to cracking. These are still structures that bear the load and are responsible for the safety of the building as a whole.

If someone had to fill the foundations or concrete tapes in parts - write in the comments for what reason and how everything exists after a while.