FIELD MANUAL For HOT MIX ASPHALT (HMA) - Mississippi ...

CHAPTER 3
QC AND QA LABORATORIES
3.1 General. All laboratories involved in the design, design verification, quality control,
and quality assurance testing of asphalt mixtures and component materials must be
fully equipped to perform the required tests. All such equipment must meet the
requirements of MDOT’s specified test methods.
3.2 QC Laboratory. Post an organization chart, including names, telephone numbers
and current certification (CAT-I, CAT-II and CMDT), of all personnel responsible
for the quality control program on the project. Post the chart in a readily visible
location.
Post all required quality control charts in a readily visible location, and maintain in
an up-to-date status. Charts may be maintained on a computer. However, updated
computer charts shall be printed and displayed at a minimum of once each
production day.
The laboratory shall be setup and calibrated prior to production. Calibration shall be
according to the procedures and frequencies given in AASHTO R 18. Inspect and
calibrate the laboratory equipment as follows:
Check calibration of Gyratory compactor according to the requirements in the
manufacturer’s manual (at a minimum, verify the angle of gyration and the load
on the specimen during compaction).
Check balances for accuracy, precision and readability in accordance with
AASHTO M 231.
Check the water baths used for specific gravity testing for constant water level,
temperature, and make sure the specimen basket does not touch the walls of the
tank each time testing is performed. Make sure a non-corrosive metal wire or a
non-absorptive cord is used to hang the basket from the bottom of the balance.
Check calibration of maximum specific gravity flask and fine aggregate
angularity cylinder.
Check vacuum pumps to confirm that the required pressure is being applied to
the flask or pycnometer.
Check accuracy of all thermometers.
Check temperature of ovens and water baths.
Rev. February 5, 2007 12