Evaluation of a modification of current microsurfacing mix design procedures

Abstract

Although microsurfacing is widely used, current tests and mix design methods mostly rely on laboratory conditions and the correlation between laboratory results and field performance is poor. Therefore, there is a need to develop new mix design procedures, specifications, and guidelines for microsurfacing mixtures. The research described in this paper intended to suggest modifications to the actual International Slurry Seal Association (ISSA) mix design procedure for microsurfacing. The first part of study reports the findings of a detailed laboratory investigation concerning the effect of asphalt emulsion, added water content, and Portland cement on the design parameters and properties of microsurfacing mixtures. A multilevel factorial design is used to assess the effect of different mixture proportions on the test responses. For this, one aggregate type, one asphalt emulsion type or grade, and one aggregate gradation were used in the study. This part of study consisted mainly of establishing a method fo...