Test on concrete*

Compaction Factor Test

➤ This test is used for the concrete possessing very low workability for which slump test is not suitable.

➤ Principle of this test is based upon finding the degree of compaction achieved by the standard amount of work done by the concrete when allowed to fall from known height.

➤ This degree of compaction is represented in terms of compaction factor that represents the density ratio.

➤ Density of concrete obtained during test to the Density of fully compacted concrete.

Slump Test

•  This is most common method.
•  Frustum having top diameter 10 cm, bottom diameter around 20 cm, height of 30 cm.
•  Concrete to be tested in filled in the mould in four layers where each layer is compacted 25 no. of times with the help of rod.
•  Mould is removed immediately by lifting it in upward direction which causes the concrete to subsidize and the subsidence of the concrete is referred as slump which may also defined as difference of the height of the mould and the top level of the subsidize concrete.
•  Higher the value of slump, more is the workability.
•  This test is not suitable for the concrete which process either very high workability or very low workability.