NETTCP Lab Testing Procedures 2

Question 1

When performing a Standard Proctor compaction test (AASHTO T 99), how many layers of soil are compacted into the mold?

Accepted Answer

3 layers

Answer

AASHTO T 99 requires 3 equal layers compacted with 25 blows of the 5.5-lb hammer per layer.

Question 2

In a sieve analysis of aggregates per AASHTO T 27, sieves must be arranged in the stack with the:

Accepted Answer

Largest opening at the top

Answer

Sieves are stacked largest opening at the top to smallest at the bottom, above the pan, so material is progressively retained on finer sieves.

Question 3

A concrete slump test per AASHTO T 119 measures which property of fresh concrete?

Accepted Answer

Workability/consistency

Answer

The slump test measures the consistency (workability) of fresh concrete by recording how much the concrete slumps after the cone is removed.

Question 4

Which test method is used to determine the liquid limit of a fine-grained soil?

Accepted Answer

AASHTO T 89

Answer

AASHTO T 89 covers the determination of the liquid limit of soils using the Casagrande liquid limit device.

Question 5

When extracting asphalt content from a bituminous mixture using an ignition oven (AASHTO T 308), the test results give:

Accepted Answer

Binder content and aggregate gradation after washing

Answer

The ignition method burns off the asphalt binder, and the remaining aggregate can be sieved to provide both binder content and aggregate gradation.

(NETTCP) New England Transportation Technician Certification Program Practice Test