ATT Sieve Analysis & Gradation 1 — Questions and Answers
Question 1: What is the purpose of performing a sieve analysis on aggregates?
- To check aggregate temperature.
- To remove fine particles.
- To determine particle size distribution. (Correct answer)
- To identify moisture content.
Correct answer: To determine particle size distribution.
Sieve analysis helps determine the particle size distribution, which affects the workability and strength of concrete.
Question 2: Which ASTM standard is used for sieve analysis of fine and coarse aggregates?
- ASTM C117
- ASTM C136/C136M (Correct answer)
- ASTM C29
- ASTM C40
Correct answer: ASTM C136/C136M
ASTM C136/C136M is the standard method used for determining the particle size distribution of aggregates through sieving.
Question 3: What is the proper procedure if material is retained on the sieve frame edge?
- Discard the retained material.
- Report it as passing.
- Push material through the mesh.
- Return it to the sieve for proper separation. (Correct answer)
Correct answer: Return it to the sieve for proper separation.
Aggregates caught on the sieve frame edge should be moved back into the sieve to ensure accurate mass distribution results.
Question 4: How is the percent passing a sieve calculated?
- Retained weight divided by sample weight.
- Sample weight minus retained weight divided by total sample weight, times 100. (Correct answer)
- Sample weight times retained weight.
- Retained weight minus sample weight.
Correct answer: Sample weight minus retained weight divided by total sample weight, times 100.
The percent passing is calculated by subtracting the cumulative retained weight from the total sample and dividing by the total, then multiplying by 100.
Question 5: What is the maximum allowable material loss during sieve analysis per ASTM C136?
- 0.5%
- 0.2%
- 0.3% (Correct answer)
- 1.0%
Correct answer: 0.3%
Material loss should not exceed 0.3% of the original mass to ensure the accuracy of the test results.
Question 6: Which equipment is essential for performing a mechanical sieve analysis?
- Oven
- Mechanical sieve shaker (Correct answer)
- Vacuum pump
- Moisture tester
Correct answer: Mechanical sieve shaker
A mechanical sieve shaker ensures consistent agitation of sieves for uniform separation of particle sizes.
ATT Sieve Analysis & Gradation 1
What is the purpose of performing a sieve analysis on aggregates?