Effect of Void in Mineral Aggregate (VMA) Value on Hot Asphalt Mixes for Heavy Traffic

Abstract

VMA is an indicator of mixture performance, especially the flexibility and durability of the mixture, for this reason the asphalt content must be high. In contrast to the demands of heavy traffic, pavement must be strong and stable. To meet these needs, the mixture requires a low asphalt content, so this research will modify the asphalt mixture to meet all these needs by using the appropriate VMA value as the criterion. The VMA value consists of the effective asphalt content and the volume of voids in the mix (VIM). For this reason, it is necessary to pay attention to the asphalt content value that corresponds to the correct asphalt mixture gradation so as to produce a VMA value that is suitable for heavy traffic loads. This research will evaluate asphalt mixtures with a maximum aggregate size of 1.5 inches, specifically the combined aggregate gradation and effective asphalt content. High performance asphalt mixture properties, characterized by high Marshall stability and high flow, will be decided as the design mixture as long as the VMA value is met. The correct VMA value will describe the mixture as being within the limits of adequate flexibility and strength, thereby ensuring the durability of the mixture. Evaluation of laboratory tests with variations in the thickness of the asphalt aggregate cover for a maximum grain size of 1.5 inches resulted in quite significant differences in properties, especially Marshall stability and flow values. The results of the evaluation of the overall properties of the asphalt mixture for heavy traffic obtained a Marshall stability value = 3712 kg, VMA = 14.24%, VIM = 5.0% and VFA = 65.96% with an asphalt content of 5.2%.