At Site, we will do some test for all material either sand, bricks and concrete etc., The material quality will increase the life of the structure and also resists defects.
Generally, there are a lot of testing methods followed in the construction for each material. We will see the different test methods in future posts.
So in this post, we are going to discuss the Concrete Slump Test and how to do the test on the field.
Slump Test of Concrete
Slump test is doing at the site to find out the workability and consistency of the fresh concrete. It does not give accuracy but it is useful to detect the uniformity of concrete mix.
Concrete Slump Chart
For an example a slab has planned to pour 50 cum of concrete and the allowable concrete slump is 50mm. So the slump test doing at the site to keep the same slump for the further concrete mix at batching plant
Workability of Concrete
The ability of concrete to handle, transport and placing between the formwork with minor segregation is called Workability of concrete.
Slump Test – IS code
The concrete slump test will be doing as per IS 1199.
The procedure of Slump Test
To follow the below procedure to do the concrete slump test and also we have required some apparatus for the test.
Slump Test Apparatus
- Tamping Rod – 60 Cm length
- Measurement Scale
- Smooth Surface Pan
- Slump Cone
Size of Slump Cone
- Height – 30 Cm
- Top Diameter – 10 Cm
- Bottom Diameter – 20 Cm
- Dia of the Tamping rod – 16mm
All the apparatus should be free from moisture or any other effluent and also it should be dry.
- First, place the slump cone mould over the smooth surface pan then fill the fresh concrete layer by layer up to the slump cone mould top.
- Each layer of filled concrete should be tamping up to 25 times by the tamping rod.
- Slowly remove the cone mould in the vertical direction and now the concrete falling down on the pan.
Concrete Slump Test Result
- Now measure the difference between the height of the slump cone mould to the concrete subsidence. The slump value will be measured in millimetre.
Types of Slump
When the slump cone mould removal, the concrete eventually slide down but it possessing the mould shape.
When the slump cone mould removal, the half portion of the concrete slides down on the pan is called Shear slump and will do the retest.
When the slump cone mould removal, the concrete fully fell on the pan is called Collapsed slump and it is not suitable for pouring.
It states that the concrete was too stiff and having the less water-cement ratio. The concrete was not falling down on the pan when removing the mould, it is called zero slump.
We hope now you understand well about the Slump Test of Concrete and you may interest to know how to calculate the concrete material.