Abstract:
Incorporating iron tailings (ITs) into asphalt represents a new method for waste-to-resource conversion. The objective of this study is to evaluate the fatigue performance of ITs as fillers in asphalt mastic and investigate the interaction and interfacial adhesion energy between asphalt and ITs. To achieve that, the particle size distributions of two ITs and limestone filler (LF) were tested through a laser particle size analyzer; the morphology and structure characteristics were obtained by scanning electronic microscopy (SEM), the mineral compositions were conducted through X-ray diffraction (XRD), and the chemical compositions were tested through X-ray Fluorescence Spectrometer (XRF). Furthermore, the fatigue properties of asphalt mastic and the interaction between asphalt binder and mineral fillers (ITs and LFs) were evaluated by Dynamic Shear Rheometer (DSR). The interfacial adhesion energy between ITs and asphalt binder were calculated through molecular dynamics simulation. In the end, the correlation between the test results and the fatigue life is established based on the gray correlation analysis, the environmental and economic benefits of iron tailings asphalt pavement are further evaluated. The results show that the particle size distribution of ITs is concentrated between 30 μm and 150 μm, and the main component is quartz. ITs have rich angularity and a higher interaction ability with asphalt. The adhesion energy of iron tailings filler to asphalt is less than that of limestone. The correlation degree of the interfacial adhesion energy and interaction between asphalt and mineral filler with asphalt mastic fatigue life is close to 0.58. Under the combined action of interaction ability and interfacial adhesion energy, the fatigue life of IT asphalt mastic meets the requirements. ITs as a partial replacement for mineral fillers in asphalt pavement have great environmental and social effectiveness.
摘要:
将铁尾矿(IT)掺入沥青中代表了一种将废物转化为资源的新方法。这项研究的目的是评估IT作为沥青胶泥中填料的疲劳性能,并研究沥青与IT之间的相互作用和界面粘附能。要做到这一点,通过激光粒度分析仪测试了两种ITs和石灰石填料(LF)的粒度分布;通过扫描电子显微镜(SEM)获得了形貌和结构特征,矿物组成通过X射线衍射(XRD)并通过X射线荧光光谱仪(XRF)测试化学成分。此外,通过动态剪切流变仪(DSR)评估了沥青胶泥的疲劳性能以及沥青结合料与矿物填料(IT和LFs)之间的相互作用。通过分子动力学模拟计算了IT与沥青结合料之间的界面粘附能。最后,基于灰色关联分析,建立了试验结果与疲劳寿命的关联度,进一步评价了铁尾矿沥青路面的环境效益和经济效益。结果表明,ITs的粒径分布集中在30~150μm之间,主要成分是石英。ITs具有丰富的棱角性,与沥青具有较高的相互作用能力。铁尾矿填料对沥青的附着能小于石灰石。沥青与矿物填料之间的界面粘附能和相互作用与沥青胶泥疲劳寿命的相关程度接近0.58。在相互作用能力和界面粘附能的共同作用下,IT沥青胶泥的疲劳寿命符合要求。ITs作为沥青路面中矿物填料的部分替代品具有巨大的环境和社会效益。