基于料堆试验的沥青混合料离析影响因素分析

Analysis on influence factors for hot mix asphalt segregation using heap test

为了分析沥青混合料的离析特性,首先提出一个利用各矿料组分在空间分布上的变异系数组合而成的离析指标,然后通过料堆试验分别对AC型和SMA型沥青混合料的5种不同级配进行试验,既验证了此指标的可靠性,同时也获得了骨料级配、沥青用量以及温度等因素对这2种沥青混合料离析程度的影响.试验结果表明:SMA相对于AC型沥青混合料有较强的抗离析性能;对于同一种混合料,温度的影响作用非常小,而沥青用量的影响则远远大于温度的影响,并与离析指标近似成线性关系.

In order to qualify the segregation of hot asphalt mixture,a mixing index was composed using the coefficient of variance of each aggregate component on distribution in space region.Then 5 gradations were tested in heaps for two sorts of asphalt mixtures-AC（asphalt concrete） and SMA（stone mastic asphalt）,by which the reliability of the segregation index was verified,and the influence degree by gradation,asphalt content and temperature were obtained additionally.Test result indicates that SMA shows higher profitability on anti-segregation than AC-type asphalt mixture;for same asphalt mixture,segregation is affected much little by temperature,but more serious by asphalt content which approximately keeps a linear relation with the segregation index.