炉渣沥青混合料配合比设计及其性能研究

Study on Mix Proportion Design and Performance of Slag Asphalt Mixture

生活垃圾焚烧炉渣与沥青混合料用的天然集料有相似的特征,在道路工程中的应用有广阔的前景。炉渣在沥青混合料的成熟应用将有效解决垃圾再利用问题。但目前关于炉渣在沥青混合料中的适用性研究仍在起步阶段,因此有必要进行炉渣沥青混合料的配合比设计研究,探究不同掺量的炉渣对沥青用量及混合料性能的影响。本文通过马歇尔设计试验、冻融劈裂试验、车辙试验和低温弯曲试验,分析不同炉渣替换比例对沥青混合料的最佳油石比、水稳定性、高温稳定性和低温抗裂性的影响。试验结果表明,最佳油石比随着炉渣替换比例的增加而增加,沥青混合料的毛体积密度和稳定度呈下降趋势,矿料间隙率和空隙率呈先减小后增加的趋势,而炉渣对沥青混合料流值的影响不大;添加适当的炉渣能够有效提高沥青混合料的水稳定性,当炉渣替换量为10%时,水稳定性的提升效果最佳;炉渣会降低沥青混合料的高温稳定性,对沥青混合料的低温抗裂性影响不大;为保证沥青混合料具有良好的路用性能,炉渣的替换比例不应超过15%。

Domestic waste incinerator slag has broad prospects in the road engineering application,which shares similar characteristics with the natural aggregate used in asphalt mixture. As a result,the mature application of slag in asphalt mixture will effectively solve the problem of garbage reuse. However,the current research on the applicability of slag in asphalt mixtures is still in its infancy,which makes it necessary to carry out research on the proportion design of slag asphalt mixtures to explore the influence of different slag content on the asphalt consumption and the performance of the mixture. Through Marshall design test,freeze-thaw splitting test,rutting test and low temperature bending test,the influence of different slag replacement ratio on optimal asphalt content,water stability,high temperature stability and low temperature crack resistance of asphalt mixture is analyzed. The test results show that with the increase of slag replacement ratio,the optimal asphalt-aggregate ratio increases,the bulk density and stability of asphalt mixture decrease,and the gap ratio and porosity of mineral materials decrease first and then increase. The slag has little effect on the flow value of asphalt mixture.What’s more,the water stability of asphalt mixture is effectively improved by adding appropriate slag,which reaches the highest point with 10% slag replacement amount. Slag reduces the high temperature stability of asphalt mixture,and has little influence on the low temperature crack resistance of asphalt mixture. In order to ensure that the asphalt mixture has excellent road performance,the proportion of slag replacement should not exceed 15%.