路用高抗滑集料耐磨性能评价与机理分析

Wear Resistance of Highly Anti-skid Aggregate for Pavement: Evaluation and Mechanism Analysis

集料耐磨耗性能对沥青路面抗滑性能起着决定性作用。采用洛杉矶磨耗试验研究了煅烧铝矾土、玄武岩和花岗岩集料的磨耗损失率和集料形态特性参数随磨耗次数的变化规律;利用皮尔森相关系数分析了集料磨耗损失率和形态特征参数的相关性,并构建了磨耗损失率与分形维数变化率及维氏硬度的关系模型;采用SEM和XRD测试手段分析了集料的耐磨机理。结果表明,88#煅烧铝矾土集料的抗磨耗性能明显优于75#煅烧铝矾土、玄武岩和花岗岩,其主要抗磨耗成分为刚玉和莫来石;所构建的模型能够较好地反映出集料磨耗损失率与分形维数变化率及维氏硬度的关系。研究成果为路面抗滑性能的提升与持久提供了新思路。

The abrasion resistance of aggregates plays a decisive role in the anti-skid performance of asphalt pavement.The Los Angeles abrasion test(LA)was carried out to investigate the abrasion loss rate of the calcined bauxite,basalt and granite aggregates,and the variation of their morphological characteristics with the abrasion cycles.Moreover,the Pearson correlation coefficient was used to analyze the abrasion loss rate and morphological characteristics of the aggregates.Accordingly,the correlation model of the fractal dimension change rate and Vickers hardness of aggregates as a function of the abrasion loss rate was established.Further,the abrasion mechanism of aggregates was analyzed by means of SEM and XRD.As can be seen from the results,88#calcined bauxite aggregates exhibit exceptionally superiority in abrasion resistance compared to 75#calcined bauxite,basalt and granite.Corundum and mullite constitute were the main abrasion-resistant components in 88#calcined.The established model is able to well describe the relationship of aggregate abrasion loss rate with fractal dimension change rate and Vickers-hardness.In conclusion,this research results provide a novel approach for improving and maintaining the anti-skid performance of pavement.