Sukkari Alaa, Al-Khateeb Ghazi, Zeiada Waleed, Ezzat Helal
Department of Civil and Environmental Engineering, College of Engineering, University of Sharjah, Sharjah, UAE.
Department of Civil Engineering, Jordan University of Science and Technology, Irbid, Jordan.
Sci Prog. 2024 Oct-Dec;107(4):368504241300198. doi: 10.1177/00368504241300198.
Asphalt pavements are consistently subjected to environmental and loading conditions that affect their durability, such as oxidative aging. Modification of the pavements assists in reducing the aging-induced stiffness. One of these solutions is crumb rubber (CR)-modified warm mix asphalt (WMA) binders. This study aims to assess the long-term performance and effects of aging on CR-modified WMA binders through a series of physical, rheological, and chemical tests. 2% and 4% of Sasobit, a wax-based additive, and 1.5% and 3% of Zycotherm, a nano-based chemical additive, with 10%, 15%, and 20% CR, were utilized. The binders were aged using a rolling thin film oven (RTFO) and pressurized aging vessel. The unaged and long-term aged asphalt binders were tested. Rheological properties, using master curves and zero shear viscosity, physical properties measured through elastic recovery, along with chemical analysis using Fourier transform infrared (FTIR) spectroscopy, were carried out on the binders before and after aging. Based on the physical and rheological aging indices, Sasobit-modified asphalt binders exhibited superior resistance to aging and rutting compared to Zycotherm-modified binders. Specifically, the Sasobit 4% and 20% crumb rubber blend showed the highest resistance to physical aging, while Zycotherm-modified binders demonstrated improved chemical aging resistance. Adding crumb rubber significantly enhanced the stiffness and elasticity of the asphalt binders, further reducing the effects of aging. FTIR analysis confirmed that Sasobit and crumb rubber reduced oxidation and volatile component loss during aging.
沥青路面始终受到影响其耐久性的环境和荷载条件的作用，比如氧化老化。对路面进行改性有助于降低老化引起的刚度。其中一种解决方案是采用橡胶粉（CR）改性温拌沥青（WMA）结合料。本研究旨在通过一系列物理、流变学和化学试验，评估橡胶粉改性温拌沥青结合料的长期性能以及老化的影响。使用了2%和4%的Sasobit（一种蜡基添加剂）以及1.5%和3%的Zycotherm（一种纳米基化学添加剂），同时添加了10%、15%和20%的橡胶粉。结合料采用旋转薄膜烘箱（RTFO）和压力老化容器进行老化处理。对未老化和长期老化的沥青结合料进行了测试。在老化前后的结合料上进行了流变性能测试（使用主曲线和零剪切粘度）、通过弹性恢复测量的物理性能，以及使用傅里叶变换红外（FTIR）光谱进行的化学分析。基于物理和流变学老化指标，与Zycotherm改性结合料相比，Sasobit改性沥青结合料表现出更优异的抗老化和抗车辙性能。具体而言，4%的Sasobit和20%的橡胶粉混合物表现出最高的抗物理老化性能，而Zycotherm改性结合料则表现出更好的抗化学老化性能。添加橡胶粉显著提高了沥青结合料的刚度和弹性，进一步降低了老化的影响。FTIR分析证实，Sasobit和橡胶粉减少了老化过程中的氧化和挥发性成分损失。
