基于AFM与分子动力学的改性泡沫沥青性能研究

Research on Performance of Modified Foamed Asphalt Based on AFM and Molecular Dynamics

针对泡沫沥青与集料黏结力较弱的问题,通过添加抗剥落剂对沥青进行改性。采用原子力显微镜(Atomic Force Microscope,AFM)观测与分子动力学模拟相结合的方式,在微观角度分析了抗剥落剂的作用机理。结果表明,抗剥落剂改性泡沫沥青的蜂状结构与光滑结构的黏附力和DMT模量都高于普通泡沫沥青。采用MS软件模拟基质沥青添加抗剥落剂前后沥青发泡过程。模拟结果表明,改性泡沫沥青各个参数都有所提升,并且水分子在改性泡沫沥青中扩散系数比基质沥青高34%。研究结果显示,抗剥落剂的添加可以增强泡沫沥青胶浆的黏结力,从而提高泡沫沥青混合料的水稳性。

Aiming at the weak adhesion between foamed asphalt and aggregates,the asphalt is modified by adding anti-stripping agent.Atomic Force Microscope(AFM)observation combined with molecular dynamics simulation is used to analyze the action mechanism of the anti-stripping agent from a microscopic point of view.The results show that the adhesive force and DMT modulus of the honeycomb structure and smooth structure of the anti-stripping agent-modified foamed asphalt are higher than those of ordinary foamed asphalt.The MS software is used to simulate the foaming process of the matrix asphalt before and after adding the anti-stripping agent.The simulation results show that,all parameters of the modified foamed asphalt are improved,and the diffusion coefficient of water molecules in the modified foamed asphalt is 34%higher than that of the base asphalt.The research results prove that the addition of anti-stripping agent can enhance the cohesion of foamed asphalt mortar,thereby improving the water stability of foamed asphalt mixture.