To remove the base "under zero" - means to make so that all points of its surface was located in one horizontal plane. It is necessary to remove the base "under zero" directly during its filling. So it turns out simpler, quicker, and stronger. However there are cases when it does not become in due time and therefore it is necessary to level already ""grabbed"" concrete.
It is required to you
- - cement;
- - sand;
- - armature;
- - boards for timbering;
- - construction tool (trowel, shovel, axe and so forth);
- - cord;
- - hydrolevel or flexible hose.
Instruction
1. Removal of the base "under zero" during its zalivkipostavta marker or chalk in one of corners of the flooded base on timbering inside mark of the planned surface (zero point). Define by hydrolevel and note similar zero points in other corners of the base.
2. In the absence of hydrolevel it is possible to expose zero points in corners by means of normal hose. For this purpose arrange the ends of hose in two verified corners. Fill in in it water, watching that in it it was not formed air locks. Establish edge of one end of hose precisely at the level of starting zero point.
3. Lifting or lowering the second end, achieve that water in the first end was established at the level of edges of hose (i.e. at the level of starting zero point). Record position in which water in the second end of hose was set. This situation corresponds to the level of zero point. Note it on timbering.
4. Make two vertical in each corner of the base has spent on drink in timbering so that they were located in the middle of base walls, and their lowest point was flush with zero points. If now you pull cord through the corresponding pro-saws, it will precisely note zero level of surface of the base.
5. Fill in in timbering concrete mix to the level of the tense cords. Thus, your base will be removed "under zero".
6. Removal "under zero" already ready to fundamentaproverta the hydrolevel or hose the provision of all corners of the base on height, having taken one of them for initial. Make the digital marks reflecting the provision of this corner rather initial in all corners. (For example, "-50" or "+30" will mean that this corner is 50 mm lower or 30 mm higher than initial corner).
7. Establish on base top the timbering consisting of two boards which lower edges cover the base from two parties and top are connected through pro-rates which length is equal to base thickness.
8. Note in all corners on timbering inside zero points to which it is necessary to flood the base, proceeding from the actual position of corners defined in the previous step. Carrying out this operation, keep in mind that the minimum thickness of dozalivayemy fragment of the base has to be not less than 30-40 mm. Too thin concrete layer will be fragile. Make pro-saws in timbering that their lower edge were at the level of grade levels (how it has been made in step 3).
9. Install fittings in timbering. Prepare sand-cement mix with ratio 1:3 or 1:4. Moisten the surface of the base with water and lay mix in timbering. Check compliance of surface to zero level the cord stretched through pro-saws.