ATT Materials Finer Than No. 200 Sieve (Washing Test) 2

Question 1

For coarse aggregate with a nominal maximum size of 1 in., what minimum sample mass is required for the ASTM C117 washing test?

Accepted Answer

2000 g

Answer

ASTM C117 requires a minimum 2000 g (2 kg) sample for coarse aggregate with a 1-in. nominal maximum size.

Question 2

When combining results of the ASTM C117 wash test with a dry ASTM C136 sieve analysis, how is the total percent passing the No. 200 sieve reported?

Accepted Answer

The wash test value is used as it captures more fines than dry sieving

Answer

The ASTM C117 wash test captures fines adhered to particles that dry sieving misses, so it yields a higher and more accurate value for material finer than No. 200.

Question 3

What is the purpose of using a large enough container during the washing operation in ASTM C117?

Accepted Answer

To allow complete immersion and vigorous agitation without losing aggregate over the rim

Answer

Using a container large enough to submerge the sample fully and agitate vigorously prevents coarse particles from spilling over the rim and being counted as fines.

Question 4

How many times should washing and decanting be repeated per ASTM C117 until the process is considered complete?

Accepted Answer

Until the wash water is clear

Answer

ASTM C117 requires repeated washing and decanting until the wash water is clear, indicating all fines have been removed.

Question 5

Which sieve must be placed beneath the No. 200 sieve to prevent damage during the ASTM C117 wash procedure?

Accepted Answer

No. 100 sieve

Answer

A No. 100 sieve is placed beneath the No. 200 sieve to protect it from damage caused by the force of the wash water stream.

(ATT) ACI Aggregate Testing Technician Practice Test

(ATT) ACI Aggregate Testing Technician Practice Test

ATT Materials Finer Than No. 200 Sieve (Washing Test) 2