Slump test....

There are three types of slump that may occur in slumps test, namely, true slump, shear slump and collapse slump. True slump refers to general drop of the concrete mass evenly all around without disintegration. Shear slump implies that the concrete mix is deficient in cohesion. Consequently, it may undergo segregation and bleeding and thus is undesirable for durability of concrete. Collapse slump indicates that concrete mix is too wet ad the mix is deemed to be harsh and lean.

slump test,

The test has been typically used in precast operations and at large construction sites. Some of the work imparted into the concrete is lost in friction between the hoppers and the concrete. The magnitude of this friction varies between different concrete mixtures and may not reflect field conditions.The compaction factor test gives more information (about compactability) than the slump test,

Effect of water addition on slump and strength of concrete