The Aggregate Impact value of the aggregate used for _______
- AConcrete for ordinary use should not be more than 45 %.
- BRoad Pavements Concrete is less than 30 %.
- CRunway Concrete is less than 30 %.
- DAll the options are correctCorrect
Solution
Concept
Aggregate impact value limits for concrete
Formula
NONE
Step-by-step solution
1. Aggregate impact value measures the resistance of aggregates to sudden shock or dynamic impact loading. 2. Standard specifications require a maximum impact value of 45 percent for non-wearing surfaces or ordinary concrete. 3. For wearing surfaces subject to dynamic impacts like road pavements and airport runways, it must not exceed 30 percent, making all given statements correct. Answer: D
Explanation
The Aggregate Impact Value measures the resistance of aggregates to sudden impact or mechanical shock. Permissible limits state that the impact value should not exceed 45 percent for general concrete work and 30 percent for wear-resistant concrete in road pavements and airport runways. Since all the statements correctly describe these standard limits, option D is the correct choice.
Why the other options are wrong
A) Option A is correct, but options B and C are also valid limits for aggregate impact value. B) Option B is correct, but options A and C are also valid limits for aggregate impact value. C) Option C is correct, but options A and B are also valid limits for aggregate impact value.
Shortcut
Aggregate Impact Value max limit = 45% for ordinary concrete, 30% for pavements.
Common mistake
Selecting a single specific application limit instead of recognizing that all given aggregate impact value limits are correct.
Correct answer: D) All the options are correct