Analysis of Aggregate Types with Micro-texture and Macro-texture Characteristics of Asphalt Mixture in Indonesia

Abstract

Background: Micro-texture and macro-texture are two essential parameters that functionally evaluate friction on asphalt pavement surface. While micro-texture indicates the irregularity of aggregate using British Pendulum Tester (BPN), macro-texture shows the larger irregularity of asphalt mix surface using Mean Texture Depth (MTD). Both micro-texture and macro-texture contribute to increased skid resistance value, which is needed for road to meet the safety qualification. Aim: This study aims to investigate the effect of local aggregate types and aggregate proportion (%) on asphalt mix on pavement textures (micro and macro-texture). Methods: Laboratory experiments were conducted on four types of local aggregates (A, B, C, and D), which were carried from West Java, Indonesia, and aggregate has a different characteristic to each other. In addition, three asphalt mix types (SMA-fine, AC-WC, and HRS-WC), each containing varying proportion (%) of aggregates, were investigated to analyze change in texture on asphalt mix surface. Statistical analysis with two-way ANOVA was carried out to investigate the significance of aggregate type and asphalt mix type on pavement surface. Results: The results showed that each aggregate exhibited different characteristics chemically and mechanically. Four types of local aggregate possessed distinctive characteristics for the asphalt mix performance (i.e., OAC and density) and pavement textures. Statistically, it was clearly found that both aggregate type and asphalt mix type were strongly related to pavement texture. Conclusion: Therefore, the aggregate type and asphalt mix type with varying aggregate proportions (%), such as coarse aggregate (CA), aggregate-fine (FA), and filler (FF), affect the micro-texture and macro-texture.