CCIL Asphalt Mix Compliance Testing 5

Question 1

What does the Dynamic Modulus (|E*|) test measure in asphalt mixture characterization?

Accepted Answer

Stiffness of the mix over a range of temperatures and frequencies

Answer

Resistance to moisture damage

Answer

Fracture toughness at low temperatures

Answer

Permanent deformation under repeated loading

Question 2

Which method is commonly used to reduce the particle size of an asphalt mix sample to a representative test portion?

Accepted Answer

Mechanical splitter or riffle box

Answer

Quartering

Answer

Random sampling from one corner

Answer

Skimming the top layer

Question 3

In Superpave performance grading, what does the low-temperature binder grade (e.g., -28 in PG 64-28) represent?

Accepted Answer

The lowest pavement temperature at which the binder meets cracking criteria

Answer

Minimum mixing temperature

Answer

Minimum air temperature during construction

Answer

Temperature at which binder becomes brittle

Question 4

What standard technique is used to verify the calibration of a Superpave Gyratory Compactor (SGC) for height measurements and angle of gyration?

Accepted Answer

AASHTO PP 60 verification procedure with a calibration fixture

Answer

Using a certified reference specimen of known dimensions

Answer

Visual inspection of compaction plates

Answer

Comparing output with a Marshall hammer

Question 5

Which parameter measured by the Bending Beam Rheometer (BBR) at low temperature is most critical for predicting thermal cracking resistance?

Accepted Answer

Stiffness (S) and creep rate (m-value)

Answer

Viscosity at 60°C

Answer

G*/sin δ at 10 rad/s

Answer

Elastic recovery at 25°C

Question 6

When a contractor submits a Job Mix Formula (JMF) for approval, which document typically defines the acceptable production tolerances around the JMF target values?

Accepted Answer

Project Special Provisions or Standard Specifications

Answer

AASHTO T 209 test report

Answer

Superpave Mixture Design Report only

Answer

The aggregate source quarry certification

Question 7

Which test procedure is used to evaluate the effect of short-term aging on asphalt binder prior to mix design?

Accepted Answer

Rolling Thin Film Oven Test (RTFOT)

Answer

Pressure Aging Vessel (PAV)

Answer

Thin Film Oven Test (TFOT)

Answer

Rotational Viscometer at 135°C