国内外沥青混合料矿粉指标调研及矿粉pH值指标分析

Investigation of Mineral Powder Index of Asphalt Mixture at Home and Abroad and Analysis of Mineral Powder pH Value Index

为探究我国现行规范中矿粉指标的合理性,完善我国矿粉评价体系,文章首先对国内外矿粉指标进行了调研分析对比其差异,然后对矿粉pH值的测定方法进行了研究,最后通过选用两种酸碱度不同的矿粉,制备SMA-13沥青混合料,并进行各项性能试验对比,分析其性能差异。试验结果表明:不同实验条件(矿粉与水的比例、静置时间)并不会对矿粉的p H值测定结果造成很大影响,为保证检测结果的准确性,可以将矿粉与水的比例1∶1、静置时间30 min设置为矿粉pH值检测的试验条件;高碱性矿粉可以一定程度上改善沥青混合料的高温性能和水稳定性,但对低温性能影响不明显;可将矿粉pH值纳入我国矿粉性能评价体系中,弥补矿粉化学性质方面指标的缺失。

In order to explore the rationality of the mineral powder index in the current specifications and improve the evaluation system of mineral powder in China,this paper first investigates and analyzes the differences of the mineral powder index at home and abroad,and then studies the determination method of the pH value of the mineral powder.Finally,two kinds of mineral powder with different pH are selected to prepare SMA-13 asphalt mixture,and various performance tests are carried out to compare and analyze their performance differences.The test results show that different test conditions(the ratio of mineral powder to water,standing time)will not have a great impact on the pH value determination results of mineral powder.In order to ensure the accuracy of the detection results,the ratio of mineral powder to water 1∶1 and the standing time 30 min can be set as the test conditions for the pH value detection of mineral powder.High-alkaline mineral powder can improve the high-temperature performance and water stability of asphalt mixture to a certain extent,but it has no obvious effect on low-temperature performance.The pH value of mineral powder can be incorporated into the performance evaluation system of mineral powder in China to make up for the lack of index on chemical properties of mineral powder.