SV Technocrats India’s Slump Test is a simple and widely used method to determine the workability and consistency of fresh concrete. It measures how much a concrete cone "slumps" when the supporting mold is removed, helping engineers assess whether the concrete is too wet, too dry, or of the right consistency.
Components of the Slump Test Apparatus
Slump Cone (Abrams Cone) – A metallic frustum-shaped mold (300mm height, 200mm bottom diameter, 100mm top diameter).
Tamping Rod – A 600mm long steel rod with a 16mm diameter, used for compacting concrete in layers.
Base Plate – A flat, non-absorbent surface for conducting the test.
Measuring Scale – Used to measure the slump value (vertical settlement of concrete after removing the cone).
Testing Procedure
Prepare the Concrete Mix – Ensure fresh concrete is mixed properly.
Position the Slump Cone – Place the cone on the base plate.
Fill the Cone in Three Layers – Each layer is one-third of the cone height.
Tamping Each Layer – Use the tamping rod to compact the concrete 25 times per layer.
Remove the Cone – Lift the cone vertically in 5–10 seconds without disturbing the shape.
Measure the Slump – The difference in height between the original and slumped concrete gives the slump value (measured in mm).
Types of Slump
True Slump – Concrete retains its shape, indicating good workability.
Shear Slump – Concrete slides sideways, indicating segregation.
Collapse Slump – Concrete completely collapses, indicating excess water.
Applications
Used in concrete mix design to ensure proper workability.
Helps control water-cement ratio on-site.
Essential for quality control in road and building construction.
