Mix designs are an integral part of the overall performance of Slurry Seal, Microsurfacing and Chipseals. For mix design of Slurry Seals and Micros, there are several recommended sources including ASTM D3910, ISSA A-105 and ISSA A-143, and MS-19 Basic Asphalt Emulsion Manual. In the lab, blending of the materials that are to be used in the field is done in varying proportions to select the proper formulation. Lab tests are conducted to ensure a slurry mixture that performs well during placement and under traffic. For Chipseals, there are procedures for determining the proper quantity of asphalt binder and cover aggregate. Material properties of the stone and asphalt are first obtained, and then calculations and lab testing performed to determine the required quantities. Adjustments must be made to account for traffic volume, absorption of the binder into the existing pavement and cover aggregate, characteristics of the cover aggregate, etc.
This webinar will illustrate the mix design process first for Slurry Seal/Microsurfacing, and then move into the same for Chipseals. Discussion for each treatment will include component material analysis, proportion optimization, performance testing, final formulation adjustments and recommendations.
- Slurry Seal/Microsurfacing mix design requirements and standard methods
- Chipseal mix design requirements and standard methods
- Highlight each performance test and its purpose
- Discuss the importance of specified tolerances
- Emphasize importance of proportioning according to the job mix formula in the lab and later in the field
- Illustrate that failure to adhere to the mix design proportions will lend itself to performance issues