矿粉微观特征及其与沥青胶浆流变性能的灰度分析

Microscopic characteristics of mineral powder and gray analysis of its rheological properties with asphalt mortar

为探究矿粉的物理特征及微观结构,深入研究胶浆流变性能及矿粉对胶浆性能的影响,分析了不同类型矿粉的物理特性、化学组成及微观结构,采用不同类型矿粉及不同0.075 mm筛孔通过率矿粉制备不同掺量的沥青胶浆,利用动态剪切流变与弯曲梁流变试验对不同矿粉沥青胶浆的高低温流变性能的影响规律进行分析,借助灰色关联分析法分别探究矿粉的物理参数、微观结构参数与沥青胶浆高温、低温性能之间的关联性。试验结果表明:5种矿粉的微小孔隙数量较少,R3与R4矿粉的孔隙多为狭长型,R1、R2、R5矿粉的孔隙多是颗粒堆积形成的;随矿粉掺量的增加,沥青胶浆的整体高温性能和抗流动能力越好,而低温性能先减弱后增强;将比表面积等指标作为比较数列,相位角等指标作为参考数列,利用灰色关联分析法确定氧化物含量对高温性能影响最大,矿粉比表面积影响最小;低温条件下,矿粉粒度对蠕变劲度影响最大,平均孔径对蠕变劲度变化率影响最大。对矿粉指标的控制及其高低温特性变化的研究结果可为实际工程应用提供参考。

In order to explore the physical characteristics and microstructure of mineral powder,and to conduct an in-depth study of the rheological properties of cement paste and the influence of mineral powder on the properties of cement paste,the physical characteristics,chemical composition and microstructure of different types of mineral powder were analyzed.Using different types of mineral powder with varying pass rates through a 0.075 mm sieve,asphalt mortar with different dosages was prepared.The influence of dynamic shear rheology and bending beam rheology test on the rheological properties of asphalt cement paste at high and low temperatures was analyzed.Gray relational analysis was employed to explore the relationships between the physical parameters and microstructural characteristics of the mineral powder and the high and low-temperature performance of the asphalt mortar.The experimental results show that the five types of mineral powders have relatively few small pores.The pores of R3 and R4 mineral powders are predominantly elongated,while the pores of R1,R2 and R5 mineral powders are mostly formed by particle accumulation.With the increase of mineral powder content,the overall high-temperature performance and anti-flow ability of asphalt mortar improve,while the low-temperature performance first weakens and then strengthens.Taking specific surface area and other indicators as comparison series and phase angle as reference series,the grey relational analysis method is used to determine that oxide content has the greatest influence on high temperature performance and the specific surface area of mineral powder has the least influence.At low temperature,the particle size of mineral powder has the greatest influence on creep stiffness,and the average pore diameter has the greatest influence on the change rate of creep stiffness.The control of mineral powder index and the change of high and low temperature characteristics can provide references for practical engineering applications.