硅藻土改性沥青及其混合料路用性能试验研究

Experimental Study on the Road Performance of Diatomaceous Earth Modified Asphalt and Its Mixture

为研究硅藻土用量对沥青及沥青混合料的性能影响,以基质沥青与SBS改性沥青作为对照,基于针入度、软化点和延度试验,针对不同硅藻土用量(9%、11%、13%、15%)改性沥青的基本性能进行分析,并采用车辙试验、低温小梁弯曲试验、浸水马歇尔和冻融劈裂试验,系统探讨了硅藻土改性沥青混合料的路用性能。试验结果表明:硅藻土加入后明显提高了沥青的软化点和延度,降低了针入度;适量的硅藻土可明显提高沥青混合料的高温抗车辙能力和低温抗裂性、水稳定性,且在13%硅藻土时高温稳定性和低温抗裂性最佳;综合经济性考虑,建议硅藻土用量宜为13%。

In order to study the influence of diatomite content on the performance of asphalt and asphalt mixture,taking matrix asphalt and SBS modified asphalt as control,based on penetration,softening point and ductility test,the basic properties of modified asphalt with different diatomite content(9%,11%,13%,15%)were analyzed,and the road performance of diatomite modified asphalt mixture were discussed by rutting test,low temperature trabecular bending test,immersion Marshall test and freeze-thaw splitting test.The test results show that the addition of diatomite significantly improves the softening point and ductility of asphalt and reduces the penetration.Appropriate amount of diatomite can significantly improve the high temperature rutting resistance,low temperature crack resistance and water stability of asphalt mixture,and the high temperature stability and low temperature crack resistance are the best when 13%diatomite is used.Considering the economy,it is recommended that the amount of diatomite should be 13%.