Flow table test is used to determine the consistency of freshly mixed concrete by measuring its spread over a flat surface. Flow test is generally done in the laboratory to determine the fluidity of the concrete.
Apparatus Required for flow table test:
The main apparatus for the flow table test is a flow table made of steel sheet of thickness 1.5mm and a size of 750mm x 750mm.
Also, a tempering rod made of hardwood, measuring scale, and a metal mould (dia. at lower-end 200mm, upper-end 170mm, and height 200mm) is required.
Some other apparatus are:
- Trowels or hand scoop
- Stop-Watch (not mandatory)
- Wet-piece of cloths
Procedure for flow table test:
- Before start testing, clean the dust from the table and mould if present by using semi-wet cotton cloths.
- Place the mould in the center of the flow table usually marked.
- Now, with the help of a trowel or hand scoop pour the freshly mixed concrete on the mould in two layers. Each layer should be tamped approximately 25 times by the tampering rod.
- If excessive concrete remains on top of mould then it should be leveled off.
- Now, the mould is removed from the concrete by the steady vertically upward pull and let concrete stand on its own without any support in the shape of mould.
- The table is then raised and dropped from the height of 12.5mm about 15 times. Each drop should not be less than 2 seconds and not more than 5 seconds.
- At last, the diameter of the spread concrete is the average of 6 symmetrically distributed. And the average spread is noted.
The value of flow(%) calculated from 0 to 150%.
In this way, you can do flow table test of concrete.
Also Read: Different method for Curing of Concrete