AIM:-
- To Determine of Abrasion value of coarse aggregates
- as per IS: 2386 (Part IV) - 1963.
APPARATUS:-
- Los Angles abrasion testing machine
- IS Sieve of size - 1.7mm
- Abrasive charge - 12 nos. cast iron or steel spheres approximately 48mm dia. and each weighing between 390and 445g ensuring that the total weight of charge is 5000 +-25 gm.
- Hot Air Oven,
PREPARATION OF SAMPLE:-
- The test sample should consist of clean aggregates which has been dried in an oven at 105 to 110⁰C to a substantially constant weight and should conform to one of the gradings shown in the table below,
PROCEDURE:-
- The test sample and the abrasive charge should be placed in the Los Angles abrasion testing machine and the machine rotated at a speed of 20 to 33 revolutions/minute for 1000 revolutions. At the completion of the test, the material should be discharged and sieved through 1.70mm IS Sieve.
CALCULATION OF RESULTS:-
- The material coarser than 1.70mm IS Sieve should be washed.
- The material that passes through the 1.70mm IS Sieve should undergo washing.
- dried in an oven at a temperature of 100 to 110⁰C to a constant weight and weighed (Weight 'B').
- The proportion of loss between weight 'A' and weight 'B' of the test sample should be expressed as a percentage of the original weight of the test sample. This value should be reported as.
Aggregate abrasion value = A-B/A×100= %