Mixture Sampling and Determination of Asphalt Binder Content for Slurry Surfacing Systems

Abstract

Slurry seals and micro surfacing are two of the main preventative maintenance methods used by state and local agencies. However, there is a lack of methods for quality control/quality assurance for slurry surfacing systems. The purpose of this work is to propose a method of quality control binder content determination for slurry surfacing systems and to develop a standardized, representative field sampling procedure. The focus is to provide an accurate and timely method to ensure test results can be obtained the same day during construction. The study evaluated the feasibility of using the ignition furnace test method to determine the residual asphalt binder content of the mixes and developed a sampling conditioning protocol to eliminate moisture from the system and improve accuracy. The results showed that the ignition method can be used in combination with microwave drying of the samples to obtain rapid, reliable results. Overall, after drying, the ignition method results in an asphalt content tolerance of ±0.426% for within laboratory testing and ±1.051% for between laboratory testing of slurry surfacing materials.