为准确表达沥青混合料矿料尺寸特征,真实反映沥青混合料级配组成,采集了3种典型级配沥青混合料的切割断面、芯样曲面图像,针对传统等效法表征矿料尺寸存在的缺点,基于矿料形态特征提取了4种特征参数,并对绘制的级配曲线进行了对比分析.结果表明:相同获取方式下得到的试件图像数据分析结果具有很好的相关性;由于曲面图像在处理过程中存在颗粒被拉长现象,使所得结果准确性降低,而平断面图像所得结果则更接近设计级配曲线;与等效圆直径相比,以平均直径为特征参数的级配曲线更接近设计级配曲线,对2.36mm粒径的颗粒作适当系数修正,即可得到与设计级配较为接近的结果.因此,平断面图像的平均直径级配曲线可作为沥青混合料级配检验的优化方法.
In order to obtain an effective particle size of asphalt mixture aggregate and reflect really composition of asphalt mixture gradation,three kind of typical asphalt mixture gradations are selected to study the cross section and core surface of the specimen.Four kinds of characteristic parameters based on morphology are compared to handle the shortcoming of traditional equivalent characterization of mineral aggregate sizes.The results indicate that data analysis results of specimen image under similar obtainment have a good correlation.Processing results of flat-sectional are closer to the design grading curves comparing image acquisition of curved surface.The phenomenon exists owing to the elongated image acquisition of curved surface in the process.Gradation curves displayed by average diameter are closest to the design gradation curves.Suitable characteristic parameters of mineral aggregate are selected to reduce errors efficiently and the particle of 2.36 mm is corrected by amending.So,the picture gradation displayed by average diameters could be a better measure to test the asphalt mixture gradation.