Performance optimization and modeling of slurry seal and micro surfacing utilizing steel slag aggregates

Abstract

Harsh climate, heavy traffic, inappropriate mix design and, most importantly, use of low-quality limestone aggregates have resulted in unsatisfactory slurry seal and micro surfacing performance in the eastrn region of Saudi Arabia. The use of emulsified asphalt slurry seal and micro surfacing is convenient and preferable over the other pavement maintenance techniques because they provide all the desirable characteristics of many maintenance techniques without creating any environmental related problems. The major concern is how to improve the performance of slurry seal and micro surfacing mixes to suit local traffic and environmental conditions.

Large amounts of steel slag aggregates, a superior quality industrial aggregate with some of the desirable aggregate qualities, are being produced and put to waste every year at Hadeed company in Jubail, Saudi Arabia.

The research was initiated to understand the potential problems and identify the factors affecting the performance of slurry seal and micro surfacing. In addition, different techniques were analyzed in order to improve certain engineering characteristics of slurry seal and micro surfacing mixes. For this purpose, blending of steel slag aggregates with limestone and modification of these mixes with hydrated lime and cement was carried out after which these mixes were tested in the laboratory for performance evaluation. The obtained test data was analyzed both objectively and statistically for the identification of factors affecting the mix performance. Based upon these test results, both the test parameters and optimum mix design parameters models were generated for the different slurry seal and micro surfacing mixes. The test results indicate that the proper blending of steel slag aggregates with limestone aggregates can significantly improve the performance of slurry seal and micro surfacing mixes.