沥青混合料级配离析定量评价划分标准的研究与探讨

Quantitative Evaluation of Criteria for Asphalt Mixture Gradation Segregation

基于均匀设计理论,模拟了15种典型程度的AC-20沥青混合料离析级配,并采用复化梯形数值积分方法求得了各离析级配曲线与设计级配曲线之间的包络面积;结合物理、力学及路用性能室内试验,提出了离析级配混合料性能指标偏差度的概念,建立了离析级配混合料各性能指标偏差度与包络面积的线性相关关系式.结果显示:级配性能指标偏差度与包络面积成正比,所有相关系数均大于0.9,相关性良好,据此提出了按包络面积来评价混合料级配离析的定量评价标准.通过现场典型区域取样并进行力学性能与抽提试验发现,按包络面积计算得到的各性能指标偏差度均位于相应指标偏差度实测值的80%置信区间内,表明基于均匀设计理论所采用的离析级配曲线与设计级配曲线之间的包络面积对混合料级配离析进行定量评价是合理可行的,可为沥青路面级配离析病害的准确评价提供示范和参考.

Based on uniform design principles,15 kinds of typical degrees of AC-20 asphalt mixture segregation gradation were simulated.The envelop areas between each segregation gradation curve and design gradation curve were calculated by composite trapezoidal integration.Combined with the physical,mechanical and pavement performance tests in laboratory,deviation degree of performance indexes for asphalt mixture was put forward.The correlations between deviation degree and envelop areas were established,all correlation coefficients were more than 0.9which indicated that there are good positive linear relationship between deviation degree and envelop areas.The quantitative evaluation criterion was put forward in accordance with the envelope area.The test results for mechanical performance and extraction of asphalt mixture through field sampling on typical segregation regions show that all indexes deviation degree calculated by the envelope area are in 80% confidence interval of the deviation degree actually measured,it means that the envelope area evaluation criterion based on uniform design principles for quantitative assessment on the gradation segregation of the asphalt mixture is reasonable and feasible,which can provide the demonstration and reference for accurate evaluation of the asphalt pavement gradation segregation.