活化煤矸石协同胶粉改性沥青交互特性研究

Interaction Characteristics of Activated Coal Gangue Synergistic Crumb Rubber Powder Modified Asphalt

为揭示胶粉(CR)与活化煤矸石粉(AG)和轻质油(OL)3种组分对沥青黏结料宏观性能影响规律和交互作用机理,以推动固废在路面材料中的资源化应用和发展。通过响应面试验设计研究了不同组分间的交互效应,建立了3种组分梯度掺量与沥青宏观性能间的映射关系,确定了最优组分配比,从流变性能、微观角度和分子层面探明了不同组分间交互特性对沥青服役品质的协同增效机制。研究结果表明:CR的结构形态和溶胀效果对沥青的物理性能起到了决定性作用,且CR与AG和OL的交互效应明显,当CR、AG和OL的掺入量分别为17.27%、2.28%和1.34%时,沥青的常规物理性能可达到最佳;在AG和OL组分的协同作用下,胶粉可以与沥青形成稳定的复合结构,改善沥青的高温流变性能、高温抗剪切性能、中温抗疲劳损伤性能及低温柔韧性;基于分子动力学模拟发现,采用3种组分复合改性沥青,可以增强界面复合体系中的非共价键键合形式,提升其界面吸附效果,其中,氢键和范德华力在短程相互作用中占据主导地位。研究结果可为复合改性沥青技术的指向性设计与应用提供理论基础与科学指导。

We reveal the influence patterns and interaction mechanisms of crumb-rubber(CR)powder,activated coal gangue(AG)powder,and light oil(OL)components on the macroscopic performance of asphalt binder,to promote resourceful application and development of solid waste in pavement materials.The interaction between different components was investigated using a response surface experimental design.The mapping relationship between the gradient dosage of the three components and the macroscopic performance of asphalt was established,and the optimal component ratio was determined.The synergistic effect of the interaction characteristics of different components on the service quality of asphalt was investigated from the perspective of rheological performance,microscopic angle,and molecular level.The results indicate that the structural morphology and swelling effect of CR play a decisive role in the physical properties of asphalt.The interaction effect between CR,AG,and OL is evident.When the content of CR,AG,and OL were 17.27%,2.28%,and 1.34%respectively,the conventional physical properties of asphalt reached optimal levels.In conjunction with the synergistic effect of AG and OL components,the rubber powder can form a stable composite structure with asphalt,thereby improving its high-temperature rheological properties,high-temperature shear resistance,intermediate-temperature fatigue resistance,and low-temperature flexibility.The simulations of molecular dynamics revealed that the use of a ternary composite modification in asphalt enhances the non-covalent bond formation within the interfacial composite system,thereby augmenting its interfacial adsorption effects.Hydrogen bonds and van der Waals forces occupy a dominant role in short-range interactions.The study provides the theoretical basis and scientific guidance for the directional design and application of composite modified asphalt technology.