Concrete Slump Test

ASTM C143 outlines standard procedures for the determination of concrete consistency using slump test.

Equipment:

1. Slump mould

2. Tamping rod (16mm dia. x 600mm length)

3. Pan

4. Scale

5. Shovel

6. Hand scoop

Sample:

Freshly mixed concrete

Procedure:

1. Dampen the mould and place it on a flat moist pan.

2. Fill the mould with sample using hand scoop. Ensure the mould firmly held by operator by standing on the two foot pieces.

3. Fill the mould in three layers, each about 1/3 the volume of mould.

4. After filling each of these layers, rod it with 25 strokes of the tamping rod. Make sure the strokes are uniformly distributed over the cross section of each layer.

5. Strike off the surface by screeding and rolling motion of the tamping rod.

6. Remove the mould by raising it vertically. Step 1 until 6 should be completed within 2.5 minutes.

7. Place the empty mould upside down beside the concrete sample. Measure the vertical difference between the top of the mould and the displaced original center of the top of sample using scale. Round the measurement to nearest 5mm and record it as slump (mm).