Effect of adding glass fiber on the properties of asphalt mix

The continuing rapid growth in traffic, along with the rise in allowable axle loads, requires improvement of highway paving materials. In the recent decades, different types of fiber materials are utilized for improving the performance of asphalt mixture. A laboratory investigation was carried out into the effect of adding Glass Fiber (GF) on some properties of Hot Mix Asphalt (HMA) mixtures. Subsequently, five HMA specimens were prepared using the Marshall mix design method for wearing surface mix (mix 4C). Marshall Stability (MS) and flow tests were applied to the specimens. Also, MS and flow values were recorded. For the Optimum Asphalt Content (O.A.C) and different GF percentages, the Marshall parameters were calculated. Then, some special tests were conducted to measure the different mix properties, including loss of stability, wheel tracking and indirect tensile strength tests. Results of the study led to important conclusions regarding using of Glass Fiber (GF) to improve most of the properties of HMA mixtures. Finally, this study recommended a proposed mix with 0.25% GF by weight of the total mix.