Testing of bitumen loss on heating
When the bitumen 40/50 , 60/70 and bitumen 80/100 is heated it loses the volatility and gets hardened. About 50gm of the sample is weighed and heated to a temperature of 1630C for 5 hours in a specified oven designed for this test. The sample specimen is weighed again after the heating period and loss in weight is expressed as percentage by weight of the original sample. Bitumen 40/50 , 60/70 and bitumen 80/100 used in pavement mixes should not indicate more than 1% loss in weight, but for bitumen 40/50 , 60/70 and bitumen 80/100 having penetration values 150-200 up to 2% loss in weight is allowed.
