In the Aggregate impact value test, as per IS: 2386 (part IV), the test sample should pass and retain through which of the following sieve size?
Passing 12.5 mm, retained on 10 mm sieve
Aggregate Impact Value Test Sample Preparation
The Aggregate Impact Value test is a standard test performed on coarse aggregates to determine their resistance to sudden impact or shock, which is an indicator of their toughness. This property is important for aggregates used in road construction and other applications where they might be subjected to dynamic loads. The test procedure, including the preparation of the test sample, is detailed in Indian Standard IS: 2386 (Part IV) - 1963, which deals with methods of test for aggregates for concrete.Selecting the Aggregate Sample as per IS: 2386 (Part IV)
According to IS: 2386 (Part IV), the aggregate sample used for the Impact Value test must be of a specific size fraction to ensure comparable and consistent results. The standard specifies that the material for the test should be:- Washed and oven-dried.
- Aggregates that pass through a 12.5 mm sieve.
- Aggregates that are retained on a 10 mm sieve.
Analyzing the Options
Let's look at the given options based on the standard requirement:- Option 1: Passing 15 mm, retained on 10 mm sieve. This is incorrect as the upper sieve size specified in the standard is 12.5 mm, not 15 mm.
- Option 2: Passing 12.5 mm, retained on 6.3 mm sieve. This is incorrect as the lower sieve size specified in the standard is 10 mm, not 6.3 mm.
- Option 3: Passing 15 mm, retained on 6.3 mm sieve. This is incorrect as both the upper and lower sieve sizes do not match the standard.
- Option 4: Passing 12.5 mm, retained on 10 mm sieve. This exactly matches the requirement specified in IS: 2386 (Part IV) for the test sample.
The aggregate passing through the 12.5 mm sieve but retained on the 10 mm sieve is the specified fraction used in the test apparatus cup for performing the impact test.
Important Questions from Highway Materials and Maintenance
The damaged material on the surface of road which is removed by rubbing or chipping action is called:
The bitumen that is obtained as a residue during the distillation of a high-resin petroleum is called:
The Indian Road Congress (IRC) recommends what value of camber for gravel or water bound macadam road surface subject to heavy rains?
The toughness property of coarse aggregates can be assessed by conducting which laboratory experiment?
Flakiness index and Elongation index test is not applicable to aggregate sizes smaller than:
