2020-06-12
96
The mobility of a concrete mixture is the ability to spread under the influence of one's own weight. Normative document for the determination of mobility - GOST 10181.1-81.
Fig. 1. Apparatus for determination of cone sediment: 1 - the handle; 2 - the case of the device; 3 - stops; 4 - welded seam
Fig. 2. The scheme for determining the mobility of a concrete mixture
| cone | dimensions, mm | ||
| d | D | h | |
| normal | 100±1 | 200±1 | 300±1 |
| increased | 150±1 | 300±1 | 450±1 |
Method of determination
The precipitation of the cone of a concrete mixture is determined by:
1. Wipe the cone with a damp cloth and all attachments in contact with the concrete mix.
2. Place the cone on a smooth metal sheet.
3. Fill the cone with a concrete mixture through a funnel into three layers of equal height.
Each layer is sealed by a bayonet with a metal rod:
- in the usual cone.......................... 25 times
- in an enlarged cone....................... 56 times
The cone must be firmly pressed against the sheet during filling and the bayonet.
4. Cut the excess mixture.
5. Smoothly remove the cone in 3-7 seconds.
6. The precipitation of the cone of the concrete mixture is determined by laying the metal ruler with the edge to the top of the cone and measuring the distance from the lower edge of the ruler to the top of the concrete mix with an error of up to 0.5 cm.
