Evaluation of Troxler 3241-C nuclear asphalt content gauge used for Marshall specimens

Abstract

Asphalt cement content is one of the most important requirements for producing high quality hot-mix asphalt. The determination of the asphalt cement content of hot-mix asphalt by traditional methods is time consuming and hazardous. A demand for faster and safer methodes) led to the development of a nondestructive technique using nuclear technology. Measuring asphalt cement content of Marshall specimens by nuclear gauges is a new technique; this study evaluates the feasibility of using the nuclear gauges. Two hundred fifty-six specimens were prepared for this purpose. The study evaluated the effect of different parameters on the measured asphalt cement content by 3241-C Troxler nuclear asphalt content gauge. The following parameters were considered: aggregate type, aggregate gradation, air-void content, moisture content in specimens, asphalt cement content, and total specimen weight. Different calibration models were developed for different bituminous mixtures.