Steele, G. W.
Director, West Virginia State Road Commission, Charleston, West Virginia
Hudson, S. B.
Chief Engineer, Materials Research and Development, Inc., Raleigh, North Carolina
Pages: 19 Published: Jan 1969
Current methods of determining asphalt content of bituminous paving mixtures are not entirely satisfactory since they may contain relatively large experimental error. In addition, some of the test methods are not adaptable to mixtures containing large aggregate particles (black base), and others may be more time consuming or expensive than is desirable for quality assurance testing. A method of determining asphalt content is needed that will have the following features: - Precision equal to or better than current methods. - Answers available in time for reasonably prompt corrective action to be taken. - Tests performed with economically replaceable equipment without the use of expensive solvents. - Accept specimens of sufficient size to — allow testing of mixtures containing aggregate up to 2″ and — minimize variations in asphalt content due to the effect of inherent variation in aggregate gradation. This paper describes an attempt to develop such a method, based on the procedures of ASTM D-2041-67T. The sample of about 6000 grams weight is contained in a large pycnometer, filled with water plus a wetting agent. Asphalt content is determined by weight/volume relationship with the aid of charts in approximately 20 minutes. Results are compared to those obtained by use of nuclear, centrifuge and reflux equipment at two levels of asphalt content. Two operators are used in this designed experiment. The test data are analyzed by the use of statistical techniques.
testing, pycnometer, vacuum desiccator, pycnometer test, asphalt content determination, bitumen content determination, rapid asphalt content determination, rapid bitumen content determination, asphalt paving mixture test, bituminous paving mixture test, quality control of asphalt mixtures
Paper ID: STP48359S