Equipment Checklist for AASHTO T 312
Standard Method for Preparing and Determining
the Density of Hot Mix Asphalt (HMA) Specimens
by Means of the SHRP Gyratory Compactor

 
All equipment shall be inspected for compliance with appropriate dimension s, as stated in each standard, as well as to determine if it is in satisfactory operation condition (i.e. clean, tight and serviceable). Inspection shall occur at least annually, or whenever there is reason to suspect nonconformance with the standard.

 



Item SHRP Gyratory Compactor with Specimen Height Measurement and Recording Device
Description An electrohydraulic or electromechanical compactor with a ram and ram heads that are restrained from revolving during compaction, the ram axis perpendicular to the platen of compactor. The specimens shall rotate at a rate of 30.0 ± 0.5 gyrations per minute while tilted at an angle of 1.25 ± 0.02 degrees, and compacted by a pressure of 600 ± 18 kPa. The compactor shall allow the specimen mold to revolve freely on its tilted axis during gyration.
   
Calibration Item Verify height, pressure, angle, speed
Calibration Procedure As per manufacturer's instructions
Calibration Interval b) as directed by manufacturer


Item Specimen Molds
Description Inside diameter of 149.90 to 150.00 mm and height of at least 250 mm, smooth, steel walls that are at least 7.5 mm thick and hardened to at least Rockwell hardness of C48.
   
Calibration Item Verify mold dimensions and check physical condition
Calibration Procedure Measure physical dimensions
Calibration Interval 6 months


Item Ram Heads and Mold Bottoms
Description Diameter of 149.90 to 149.75 mm and height of at least 250 mm, smooth, steel walls that are at least 7.5 mm thick and hardened to at least Rockwell hardness of C48.
   
Calibration Item Verify plate dimensions and check physical condition
Calibration Procedure Measure physical dimensions
Calibration Interval 6 months


Item Balance
Description Readable to 0.1% of sample mass or better
   
Calibration Item Verify mass readings
Calibration Procedure AASHTO M 231, Class G5
Calibration Interval 12 months


Item Thermometer
Description Capable of measuring temperatures between
10 and 232 C.
   
Calibration Item Verify temperature readings
Calibration Procedure ASTM E 1, ASTM E 77
Calibration Interval 6 months


Item Oven
Description Thermostatically controlled to ± 3 C, capable of maintaining up to 176 ± 3 C
   
Calibration Item Verify temperature readings
Calibration Procedure Verify with calibrated thermometer
Calibration Interval 4 months


Item Thermometer
Description Capable of accurately measuring temperatures used in this test method
   
Calibration Item Verify temperature readings
Calibration Procedure ASTM E 1, ASTM E 77
Calibration Interval 6 months


Item Incidental Equipment
Description Flat bottom metal pans, containers, mechanical mixer (optional), scoop, spoon, trowel, spatula, gloves, paper disks, lubricating materials recommended by compactor manufacturer
   
Calibration Item Check physical condition
Calibration Procedure Visual
Calibration Interval 6 months


   
Reference the following specifications
AASHTO T 166 Bulk Specific Gravity of Compacted Bituminous Mixtures Using Saturated Surface-Dry Specimens
AASHTO T 209 Theoretical Maximum specific Gravity and Density of Bituminous Paving Mixtures