泡沫沥青混合料抗剪强度影响因素

Study on Influencing Factors of Shear Strength of Foamed Asphalt Mixture

泡沫沥青混合料抗剪强度是决定其耐久性能的关键指标之一。以沥青发泡性能、泡沫沥青用量、水泥掺量、聚丙烯纤维掺量为影响因素,通过单轴贯入试验,分析泡沫沥青混合料的抗剪强度。试验结果表明,沥青发泡性能、泡沫沥青用量、水泥掺量、聚丙烯纤维掺量对泡沫沥青混合料抗剪强度的敏感性差异较大,其中水泥掺量>聚丙烯纤维掺量>沥青发泡性能>泡沫沥青用量。沥青发泡性能、水泥掺量、聚丙烯纤维掺量与泡沫沥青混合料抗剪强度正相关,混合料抗剪强度随着泡沫沥青用量的增大呈现先增大、后减小的趋势。建议以沥青发泡性能高水平、泡沫沥青用量3%、水泥掺量1.5%、纤维掺量0.4%为泡沫沥青混合料抗剪强度的最佳组合。

The shear strength of foamed asphalt mixture is the key index to determine its durability.In order to further study the shear strength of foamed asphalt mixture,in this paper,uniaxial penetration test has beenadoptedto study the shear strength of foamed asphalt mixture by taking foaming properties of asphalt,the amount of foamed asphalt,the amount of cement and the amount of polypropylene fiber as the influencing factors.The results have shown that the sensitivity of foaming properties of asphalt,the amount of foamed asphalt,the amount of cement and the amount of polypropylene fiber to the shear strength of foamed asphalt mixture is significantly different,in which cement content>polypropylene fiber content>asphalt foam properties>asphalt foam content.The foaming properties of asphalt,the amount of cement and the amount of polypropylene fiber are positively correlated with the shear strength of foamed asphalt mixture.The shear strength of the mixture firstly increases and then decreases with the increase of the amount of foamed asphalt.It has been suggested that the best combination of the shear strength of the foamed asphalt mixture is the high foaming properties of asphalt,the amount of foamed asphalt is 3%,the amount of cement is 1.5%,the amount of fiber is 0.4%.