METHOD OF MAKING TEST CUBES FROM FRESH CONCRETE

Name of Test:- Method of Making Test Cubes from Fresh Concrete

Object:- The concrete cube is prepared from fresh concrete in order to obtain the compressive strength of concrete.

Reference Standard: BS 1881 – Part 108 – 1983

Apparatus:

· Cube mould

· Scoop

· Compacting bar of steel, weight 1.8 kg, length 380 gm, ramming face size 25 mm square

· Plasterer’s steel float

· Square mouthed shovel,

· Sampling tray

Procedure:-

Ø Empty the sample from the wheel barrow/mixer on the sampling tray.

Ø Thoroughly mix the sample by shoveling.

Ø Place cube mould on a rigid horizontal Surface.

Ø Fill concrete in mould in layers of 50mm deep( total three layers)

Ø Compact each layer with compacting bar subjected to 35 strokes per layer for 150mm cube & 25 strokes per layer for 100mm cube.

Ø After compaction of top layer, smooth it level with top mould using plasterer’s float & wipe clean the outside of mould.

Ø Keep the sample under moist condition and without any disturbance/vibration for 24 hours before demoulding

Ø Demould the cube after 24 hours and keep cubes in the curing tank under water at 20±2° centigrade