煤矸石粉与沥青的交互作用评价及其微观机理研究

Study on Interaction Evaluation and Its Micro-mechanism of Coal Gangue Powder and Asphalt

矿料与沥青的交互作用决定着沥青混合料的路用性能,为了评价煤矸石粉与沥青的交互作用能力并揭示交互作用机理,利用动态剪切流变仪(DSR)对煤矸石粉沥青胶浆的流变性能进行了测试,运用广义sigmoidal函数和WLF方程构建了沥青胶浆动态剪切模量主曲线。基于Palierne模型系数C对煤矸石粉与沥青的交互作用进行评价,提出了参数拟合法以减弱C值对煤矸石粉体积分数的依赖性,借助扫描电镜和原子力显微镜对交互作用的微观机理进行了分析。研究结果表明:通过交互作用评价系数C值比较得出煤矸石粉与沥青的交互作用强于石灰岩粉,煤矸石粉的粗糙表面及开口孔隙更容易与沥青形成嵌锁的界面结构,煤矸石粉与沥青发生交互作用后产生更多数量的“蜂状结构”,形成了密集交织的网状结构体系,从而使煤矸石粉与沥青具有更强的交互作用。

The interaction between mineral fillers and asphalt determines the road performance of asphalt mixture.In order to evaluate the interaction ability between coal gangue powder and asphalt,and reveal the interaction mechanism,rheological properties of coal gangue powder asphalt mastic were investigated by means of the dynamic shear rheometer(DSR)test.Master curves of dynamic shear modulus of asphalt mastic were constructed by generalized sigmoidal function and WLF equation.The interaction ability between coal gangue powder and asphalt was evaluated based on the coefficient C of Palierne model.A parameter fitting method was proposed to weaken the dependence of C value on the volume fraction of coal gangue powder.The interaction micro-mechanism was analyzed by using SEM and AFM experiment.The results show that coal gangue powder exhibits a stronger interaction ability with asphalt than limestone powder by the comparison of coefficient C.Coarse surface and open pores of coal gangue powder are easier to form interlocking interface with asphalt.Asphalt mastic produces more bee structures than base asphalt due to the interaction between coal gangue powder and asphalt,and forms a dense network structure system,so that coal gangue powder has a stronger interaction ability with asphalt.