ABSTRACT

In hot climate regions asphalt mixes can be designed using the classical volumetric approach supplemented by the evaluation of basic mechanical parameters. To minimize the risk of permanent deformation, composition of the mixes can be defined by selecting densely packed aggregates and low binder contents. Despite the effectiveness of such an approach, mix design systems need to be improved by including performance-based tests that focus on the evaluation of the true rutting potential of asphalt mixes. The investigation described in this paper addressed these issues by considering twelve rut-resistant asphalt mixes designed as per the requirements set in the State of Qatar. These mixes, containing neat and polymer-modified binders (PMBs), were subjected to the Hamburg Wheel-Track Test (HWTT), dynamic modulus test and flow number test. Analysis of experimental data led to tentative requirements set on the results of dry HWTTs that can be introduced in the mix design framework currently adopted in the State of Qatar. Calculation of rank correlation coefficients showed that the various tests can be employed in different conditions for the assessment of the true rutting potential of asphalt mixes.

摘要

在炎热气候地区，可以使用经典的体积方法设计沥青混合料，并辅之以基本机械参数的评估。为了使永久变形的风险降到最低，可以通过选择密集堆积的骨料和低粘合剂含量来确定混合物的组成。尽管这种方法有效，但仍需要通过包括基于性能的测试来改进混合料设计系统，这些测试重点在于评估沥青混合料的真实车辙潜力。本文所述的调查通过考虑根据卡塔尔州设定的要求设计的十二种抗车辙沥青混合料来解决这些问题。这些包含纯净和聚合物改性粘合剂（PMB）的混合物进行了汉堡车轮痕迹测试（HWTT），动态模量测试和流量测试。对实验数据的分析导致对干燥HWTT结果的初步要求，可以将其引入卡塔尔州目前采用的混合设计框架中。等级相关系数的计算表明，可以在不同条件下使用各种测试来评估沥​​青混合料的真实车辙潜力。