Tong Bilin, Habbouche Jhony, Flintsch Gerardo W, Diefenderfer Brian K
Virginia Tech Transportation Institute, Blacksburg, VA 24061, USA.
Virginia Transportation Research Council, Charlottesville, VA 22903, USA.
Materials (Basel). 2023 Dec 12;16(24):7611. doi: 10.3390/ma16247611.
The balanced mix design (BMD) constitutes a significant step forward in the pursuit of better-performing asphalt mixtures. This approach/framework offers increased innovative opportunities for the proper design and production of engineered asphalt mixtures without the need to strictly adhere to traditional volumetric requirements. The primary objective of this paper is to conduct a comprehensive investigation of the permanent deformation (rutting) behavior of surface mixtures (SMs) with conventional and high reclaimed asphalt pavement (HRAP) contents through full-scale accelerated testing under incremental loading conditions while accounting for the environmental aging effect. HRAP SMs were designed in this study, marking the initial application of Virginia Department of Transportation (VDOT) BMD special provisions, with attempts to incorporate 45% and even 60% RAP. Results showed that all BMD HRAP mixtures exhibited higher rut depths compared to the control mixture, which can be attributed to the inclusion of high binder contents aimed at enhancing cracking resistance. The asphalt pavement analyzer (APA) rut test and the stress sweep rutting tests were performed on mixtures sampled during production. Correlation analysis revealed significant and strong positive correlations between accelerated pavement testing (APT) and the multilevel laboratory rutting performance tests considered in this study. Finally, while acknowledging the limitations and all the assumptions considered in this study, the correlation analysis recommended refining the VDOT BMD APA rut depth threshold by lowering the current limit of 8 mm to 7 mm to ensure good performing mixtures from a rutting point of view.
平衡配合比设计（BMD）是在追求性能更优的沥青混合料方面向前迈出的重要一步。这种方法/框架为工程沥青混合料的合理设计和生产提供了更多创新机会，而无需严格遵循传统的体积要求。本文的主要目的是通过在增量加载条件下的全尺寸加速试验，并考虑环境老化影响，对含有常规和高再生沥青路面（HRAP）含量的表面混合料（SM）的永久变形（车辙）行为进行全面研究。本研究设计了HRAP SM，这标志着弗吉尼亚州运输部（VDOT）BMD特殊规定的首次应用，尝试掺入45%甚至60%的RAP。结果表明，与对照混合料相比，所有BMD HRAP混合料的车辙深度都更高，这可归因于为提高抗裂性而包含的高结合料含量。对生产过程中取样的混合料进行了沥青路面分析仪（APA）车辙试验和应力扫描车辙试验。相关性分析表明，加速路面试验（APT）与本研究中考虑的多级实验室车辙性能试验之间存在显著且强烈的正相关。最后，在承认本研究中考虑的局限性和所有假设的同时，相关性分析建议将VDOT BMD APA车辙深度阈值从当前的8毫米降低到7毫米，以确保从车辙角度来看混合料性能良好。
