基于分子动力学模拟的蒙脱土与沥青相互作用机理研究

Interaction Mechanism between Montmorillonite and Asphalt based on Molecular Dynamics Simulation

为系统地研究蒙脱土对沥青各项性能的影响,利用分子动力学模拟从分子角度考察了沥青和蒙脱土相互作用机理。通过改变试验过程中的温度等参数研究了蒙脱土改性沥青粘结强度的变化,通过对相互作用能进行分析,发现在60℃时沥青与蒙脱土粘结强度达到最大;同时对原子运动轨迹进行分析发现随着温度的升高蒙脱土分子的移动更加活跃,且在60℃时蒙脱土晶体层分布更为扩散,这为与沥青的相互交融创造了良好条件。但从能源节约角度考虑,采用蒙脱土对沥青进行改性时,建议在45℃条件下进行。

In order to systematically study the effect of montmorillonite on various properties of asphalt,the interaction mechanism between asphalt and montmorillonite was investigated from molecular angle by molecular dynamics simulation.The change of bond strength of montmorillonite modified asphalt was studied by changing the temperature during the test.By analyzing the action energy,the bond strength between asphalt and montmorillonite reached the maximum at 60℃;At the same time,the montmorillonite molecule is found to be more active with the increase of temperature by analysis of atomic trajectory and the distribution of the montmorillonite crystal layer is also more diffused at 60℃,which created favorable conditions for the intermixing with asphalt.However,it is recommended to prepare montmorillonite modified asphalt at 45℃for the energy saving.