基于单轴贯入的沥青混合料抗剪性能研究

Research on Shear Properties of Asphalt Mixtures Based on Uniaxial Penetration Test

设计制作8种混合料进行单轴贯入试验,利用摩尔-库伦理论计算了抗剪参数。结果表明,AC型沥青混合料最大剪应力随公称最大粒径的增加而变大;AC-16的黏聚力明显高于SAC-16,细集料含量越多,黏聚力越大;SBS改性沥青可有效改善抗剪性,其中SAC-16最大剪应力增幅为31%;内摩阻力在抗剪强度中贡献度均有增加,其中SAC-16内摩擦角增加3.27°,c/τmax从25.9%降到20.4%,贡献度增幅最大;方差分析表明沥青性质对沥青混合料的最大剪应力产生显著影响。

Eight kinds of mixture were designed and made for uniaxial penetration test,the shear parameters were calculated by Moore-Coulomb theory.The results show that the maximum shear stress of AC increases with the increase of the nominal maximum particle size.The cohesion of AC-16 is significantly higher than that of SAC-16,indicating that asphalt mixture with more fine aggregate content has more cohesive force.SBS modified asphalt can effectively improve the shear resistance and the maximum shear stress increase of SAC-16 is 31%.The contribution degree of internal friction resistance in shear strength is also improved by SBS,the angle of internal friction of SAC-16 increases by 3.27°,and c/τmax decreases from 25.9%to 20.4%,which means that the contribution degree increases the most.Analysis of variance shows that the type of asphalt has a significant effect on the maximum shear stress of asphalt mixture.