Concrete Slump Cone Test
The concrete slump cone test measures the consistency of fresh concrete before it sets. It is performed to verify the workability of freshly made concrete and, therefore, the ease with which the concrete flows.
It can also be used as an indicator of an incorrectly mixed batch. The test is popular due to the simplicity of the apparatus used and the simple procedure. The slump test is used to ensure uniformity of different concrete loads under field conditions.
A separate test, known as the flow chart, or slump flow test, is used for concrete that is too fluid (not workable) to be measured using the standard slump test, because the concrete will not retain its shape when the cone It is removed.
Concrete Slump Cone Test Apparatus and Procedure
|Damping Rod ,Slump Cone set|
The mold is placed on a smooth, horizontal, rigid and non-absorbent surface.
The mold is filled in four layers, each approximately 1/4 the height of the mold.
Each layer is rammed 25 times with a rod taking care to distribute the strokes evenly over the
cross section. After the top layer has been rolled, the concrete is leveled with a Paddle and tamping rod.
The mold is removed from the concrete immediately by slowly and carefully lifting it a vertical direction.
This allows the concrete to sink. This subsidence is known as a concrete settlement.
The difference in level between the height of the mold and that of the highest point of Sunken concrete is measured. This height difference in mm is taken as a drop of concrete.
The settlement pattern indicates the characteristics of the concrete in addition to the settlement.
value. If the concrete collapses evenly, it is called true sinking. If one of the cones slides down is called shear drop.