Time to help
The foundation is one of the most time -consuming and costly elements of building a building. Volumes used by concrete can reach several cubic meters. And there is no possibility of a single amount of building material to a lifting or prepare or prepare. There is a way out: observing a certain technology, pouring the foundation not in full at the same time, but in parts.
Formation of the foundation
A positive answer to the question is whether the foundation can be poured in parts given taking into account the features of the formation of concrete. In his formation, he passes two time stages:
grasping, during which all components of concrete are connected and react. This process cannot be violated. Its duration is from 3 hours at a temperature of 200. At lower temperatures, the start of setting occurs after 6 hours from closing, and with higher or heating – after 20-30 minutes. The beginning of the process can be accelerated or pushed by time using various additives. This value depends on the brand of concrete;
hardening or gaining such a percentage of a project fortress, which allows you to preserve all the indicators of this brand of concrete even after freezing. Subject to all technological conditions, the hardening time is 25 days, but it begins in a day, and a set of 100% of the fortress is about a year.
The time of pouring portions of concrete depends on the time of setting and hardening this material.
The main types of filling
Before filling the foundation in parts determines the time for which it is necessary to interrupt the work. The control value is taken for 12 hours:
If the break in the work will be up to 12 hours, the second layer is poured with the “hot seam” method;
If necessary, interrupt work by more than 12 hours, use the “cold seam” method.
The “hot seam” method allows you to start filling the next layer in the summer after 3 hours, in the spring and autumn after 4 hours, and in winter after 8 hours. In this case, the surface of the previous layer is covered with a protective film, which prevents concrete from above to dry until the crust.
Before pouring a new layer, it is necessary to remove concrete milk from the surface.
The “cold seam” option is characterized by an excerpt for a longer time between the shutter of individual layers. Ideally, they try to wait for the complete hardening of the already flooded part. This is due to the fact that if you can not withstand the time of hardening not only the upper crust, but the whole concrete composition, the crust may crack. But at the same time, under a new layer of concrete, cracks will not be noticeable.
Partial filling
The poured layer is necessarily cleaned of the dust and dirt that performed moisture.
Features of the technology of filling in parts
Three methods are distinguished by the technological approach that you can fill in the foundation in parts:
vertically with the separation of formwork with metal partitions into areas. Suitable for small portions of filling. Partitions are removed after solidification. Their place is indicated on the sketch that displays the entire process of working on the foundation;
horizontally taking into account the location of the reinforcement. The layer should not be equal to the level of placement of the reinforcement: it either covers it, or is below. The height of the first layer should not exceed half the height of the formwork;
at an angle that is suitable for large volumes of work. It involves separation by formwork shields at an angle of 45 0.
Only horizontal seams are used for piles, any option is suitable for the strip foundation, provided that the reinforcement is installed perpendicular to the seam.
Before the work, it is necessary to draw up a sketch and a schedule. On the sketch, they note the height of the layer, the place of the partitions, the angle of the slope, the location and orientation of the reinforcement. The temporary schedule contains information about the time of grasping and solidifying the concrete mixture and the intervals between the filling of individual layers. After pouring, each layer of concrete is thoroughly compacted and aligned.