Red mud, a waste residue of aluminium industry, was used as modified asphalt material to prepare red mud modified asphalt and red mud modified asphalt under freeze-thaw cycles. The matrix asphalt (MA), red mud modified asphalt (RMMA), and red mud modified asphalt under freeze-thaw cycles (RMMAFC) were studied by scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). Microscopic experiments were conducted to investigate the modification performance and mechanism. The modification mechanism of red mud modified asphalt was investigated using molecular dynamics simulation in this study. The results show that red mud can form a uniform and stable blending system with base asphalt after adding base asphalt. The structure of asphalt after adding red mud and adding red mud and freezing-thawing cycles does not change. The bee-structure decreases obviously with the addition of red mud by atomic force microscopy (AFM). Density decreases gradually, but bee-structure height increases obviously; bee-structure of red mud modified asphalt is destroyed after freeze-thaw cycles. Through differential scanning calorimetry (DSC), after adding red mud, heat absorption decreases. Freeze-thaw cycles greatly reduce heat absorption of red mud modified asphalt. Constructing molecular model of major components of red mud (Fe₂O₃, Al₂O₃) and asphaltene, simulation results show that the interfacial energy between asphaltene and red mud’s main components Fe₂O₃ and Al₂O₃ at −10°C, 25°C, and 170°C is stronger than that of Fe₂O₃. The results of calculating the interfacial energy of asphaltene on the chemical composition surface of red mud are negative. It can be seen that there are adsorption effects on the surface of asphaltene and red mud. Therefore, increasing the content of Al₂O₃ or decreasing the content of Fe₂O₃ in red mud is beneficial to the adsorption of asphaltene.

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红泥改性沥青改性机理的多尺度研究

铝工业废渣赤泥被用作改性沥青材料，在冻融循环下制备赤泥改性沥青和赤泥改性沥青。通过扫描电子显微镜（SEM），傅里叶变换红外光谱（FTIR），原子力显微镜（SEM）研究了基体沥青（MA），赤泥改性沥青（RMMA）和冻融循环下的赤泥改性沥青（RMMAFC）。 AFM）和差示扫描量热法（DSC）。进行了微观实验，以研究其改性性能和机理。利用分子动力学模拟研究了赤泥改性沥青的改性机理。结果表明，添加基础沥青后，赤泥可与基础沥青形成均匀稳定的共混体系。加赤泥，加赤泥和冻融循环后的沥青结构不变。通过原子力显微镜（AFM）观察，随着红泥的加入，蜜蜂的结构明显减少。密度逐渐降低，但蜂的结构高度明显增加；冻融循环后破坏了红泥改性沥青的蜂结构。通过差示扫描量热法（DSC），添加赤泥后，吸热量降低。冻融循环大大降低了赤泥改性沥青的热吸收。赤泥（铁）主要成分的分子模型构建 冻融循环后破坏了红泥改性沥青的蜂结构。通过差示扫描量热法（DSC），添加赤泥后，吸热量降低。冻融循环大大降低了赤泥改性沥青的热吸收。赤泥（铁）主要成分的分子模型构建 冻融循环后破坏了红泥改性沥青的蜂结构。通过差示扫描量热法（DSC），添加赤泥后，吸热量降低。冻融循环大大降低了赤泥改性沥青的热吸收。赤泥（铁）主要成分的分子模型构建₂ O ₃，Al ₂ O ₃）和沥青质，模拟结果表明，沥青质与赤泥主要成分Fe ₂ O ₃和Al ₂ O ₃在-10°C，25°C和170°C时的界面能为比Fe ₂ O _3强。赤泥化学成分表面沥青质界面能的计算结果为负。可以看出沥青质和赤泥表面有吸附作用。因此，增加Al ₂ O ₃的含量或减少Fe ₂ O ₃的含量 在赤泥中有利于沥青质的吸附。