粉煤灰-聚酯纤维沥青混合料低温性能研究

Research on Low Temperature Performance of Fly Ash-polyesterFiber Asphalt Mixture

为研究粉煤灰对聚酯纤维沥青混合料低温性能的影响,进行了不同粉煤灰掺量(0%、20%、40%、60%、80%、100%)和不同聚酯纤维掺量(0%、0.3%、0.35%、0.4%、0.45%、0.5%)下的沥青混合料低温性能试验,并对试验结果做了分析和拟合,在不损害原沥青混合料低温性能的情况下,得出了粉煤灰和聚酯纤维的最佳掺量。试验结果表明:粉煤灰能使沥青混合料的低温抗拉强度有所下降;且随着粉煤灰掺量的增加,低温抗拉强度下降幅度越大。聚酯纤维能够提高沥青混合料的低温抗拉强度,可以用来弥补掺加粉煤灰造成的抗拉强度损失。聚酯纤维掺量为0.4%,粉煤灰掺量为40%时,沥青混合料劈裂抗拉强度与普通沥青混合料相当。这样,既可保证普通沥青混合料的劈裂抗拉性能,又能将粉煤灰充分地利用起来。

To study the influence of fly ash on the low temperature performance of polyester fiber asphalt mixture,the low temperature performance test of asphalt mixture with different fly ash content(i.e.0%,20%,40%,60%,80%,100%)and different polyester fiber content(i.e.0%,0.3%,0.35%,0.4%,0.45%,0.5%)was carried out,and the results were analyzed and fitted.The optimal content of fly ash and polyester fiber was obtained without damaging the low-temperature performance of the original asphalt mixture.The results show that,the fly ash can reduce the low-temperature tensile strength of the asphalt mixture;and with the increase of the fly ash content,the lower the low-temperature tensile strength decreases.Polyester fiber can improve the low-temperature tensile strength of asphalt mixture and can be used to compensate for the loss of tensile strength caused by adding fly ash.The splitting tensile strength of asphalt mixture is equivalent to that of ordinary asphalt mixture when the content of polyester fiber is 0.4%and the content of fly ash is 40%.In this way,the split tensile performance of ordinary asphalt mixture can be guaranteed,and the fly ash can be fully utilized.