Float test of bitumen 40/50,60/70 and bitumen 80/100
Normally the consistency of bituminous material can be measured either by penetration test or viscosity test. But for certain range of consistencies, these tests are not applicable and Float test is used.
The apparatus consists of an aluminum oat and a brass collar filled with bitumen 40/50 , 60/70 and bitumen 80/100 to be tested. The specimen in the mould is cooled to a temperature of 50C and screwed in to oat. The total test assembly is floated in the water bath at 500C and the time required for water to pass its way through the specimen plug is noted in seconds and is expressed as the oat value.