|The consistency of concrete is measured by the slump test. The test should not take longer than 10 minutes because concrete loses its slump over time. A metal slump cone mould, steel rod and ruler are used to measure the slump. The slump cone mould is 300 mm high, 200 mm wide at the base diameter, and 100 mm wide at the top diameter; and the hemispherically shaped tipped steel rod is 16 mm wide (diameter) and 600 mm long. The ruler is metric or imperial. The slump cone mould is filled with 3 equal layers of concrete after it has been dampened and placed on a solid flat surface. Each layer is rodded 25 times before the next layer is placed. After rodding, the first layer will be 70 mm in depth, the second layer will be 160 mm, and the third layer will be filled to overflowing. The last layer is struck off and the slump cone mould is removed slowly and upright. After the concrete settles to a new height, the empty slump cone mould is placed next to the concrete. The slump is measured,with an accuracy of 10 mm, from the slump cone mould top to the top of the settled concrete. Fluid concrete has a high slump and stiff concrete has a low slump.|
Materials In Concrete.
2.Concrete Aggregates - Concrete Slump.
3.Concrete Placement - Vibration - Hydration.
4.Types of Portland Cement - Concrete Moisture & Cracking.
5.Watertight Concrete - Supplementary Cementing Materials.
6.Supplementary Cementing Materials.
7.Chemicals That Damage Concrete.
8.Concrete Aggregate Properties.
9.Angular & Smooth Aggregate Properties.
12.Air Entraining Admixtures.
13.Air Entraining Admixtures Continued.
14.Conditions Affecting Concrete Air Volume.
15.Superplasticizers & Other Admixtures.
16.Ordering & Mixing Concrete.
17.Concrete Mixing - Subgrade Preparation.
18.Subbase Preparation - Concrete Placement.
22.Hot Weather Concreting.
23.Cold Weather Concreting.
24.Concrete Slump Test.