Evaluation of the Role of Fibers in Performance of Microsurfacing Mixtures

Microsurfacing mixtures are applied as efficient surface treatment mixes for rehabilitation of pavement surfaces. Unlike their several benefits, microsurfacing mixes lack resistance to heavy traffic loading and low temperature cracking. Among various methods of increasing their resistance, the application of different fiber types was of interest of many researchers. In this research, the effects of various fiber types, including modified Plyolefin-Polypropylene, Forta and Fiberglass at 0.1, 0.2 and 0.3 percentage levels of the mix were investigated. Cohesion, Wet Track Abrasion, Loaded Wheel and Flexural Beam tests were carried out on different mix compositions containing various fiber types. Experimental results showed that performance of microsurfacing mixtures is significantly improved with the addition of fibers. The results showed that the addition of %0.2 modified Plyolefin-Polypropylene, %0.2 Forta and %0.2 Fiberglass separately, resulted in major improvements in cohesion and abrasion resistance of mixes. Mixes containing %0.1 Forta, %0.1 modified Plyolefin-Polypropylene and %0.2 Fiberglass, compared with conventional microsurfacing mixtures, showed the least rut values. Analyzing the results of the cohesion and loaded wheel tests, it was observed that specimens exhibiting highest cohesions resulted in less rutting. In flexural beam testing, it was observed that the application of Forta fiber resulted in the best performance against cracking. The application of this fiber in mixtures increased toughness values at 25, 0 and -10 °C to %15.3, %33.1 and %67.2, respectively.