ABSTRACT

Crumb Rubber Modified (CRM) binder specifications has historically relied on empirical testing with limited relationships to pavement performance. Several fundamental rheological tests have been developed in the Dynamic Shear Rheometer (DSR) with demonstrated correlation to field performance. However, these tests are conducted on aged materials to simulate in service performance through laboratory aging protocols that are not suitable for CRM binders. With the growing need for reliable performance-based characterisation of asphalt binders, a new approach to evaluating CRM binder performance is needed. This study utilises an experimental approach to introduce a new analysis methodology for evaluating performance characteristics of CRM binders. A new rheological parameter ‘Crossover Temperature’ is introduced and defined as the temperature at which the stiffnesses of CRM and residual (rubber filtered out after interaction) binders coincide. Crossover Temperature provided strong correlations to CRM binder fatigue and rutting characteristics, without the need for binder aging or micromechanical modelling. A wide range of base asphalt binders and CR sizes were utilised in this study. This parameter is recommended for Quality Control screening of CRM binders.

摘要

改性橡胶 (CRM) 粘合剂规格历来依赖于经验测试，与路面性能的关系有限。已在动态剪切流变仪 (DSR) 中开发了几项基本流变测试，证明与现场性能相关。但是，这些测试是在老化材料上进行的，以通过不适用于 CRM 粘合剂的实验室老化协议来模拟使用性能。随着对基于可靠性能的沥青粘合剂表征的需求不断增长，需要一种评估 CRM 粘合剂性能的新方法。本研究利用实验方法引入了一种新的分析方法，用于评估 CRM 粘合剂的性能特征。引入了一个新的流变参数“交叉温度”并将其定义为 CRM 和残余（相互作用后过滤掉的橡胶）粘合剂的刚度一致的温度。交叉温度与 CRM 粘合剂疲劳和车辙特性具有很强的相关性，无需粘合剂老化或微机械建模。在这项研究中使用了广泛的基础沥青粘合剂和 CR 尺寸。建议将此参数用于 CRM 粘合剂的质量控制筛选。