【摘要】 为研究薄表层沥青混合料的骨架特性,同时为保证公称最大粒径9. 5 mm(UTL-10)矿料级配的稳定性,在4. 75 mm与9. 5 mm筛孔中间增设7. 5 mm筛孔,通过捣实密度试验分析了不同粗集料配比的集料骨架间隙率(VCA)。同时,提出了利用粗集料-沥青胶浆试件的单轴贯入试验来研究不同组合的粗集料抗剪强度相关参数,确定了薄表层粗集料的级配设计控制指标,最终给出了薄表层粗集料的推荐配比范围。结果表明:集料内摩阻角φ能够很好地反映粗集料级配的骨架强度稳定性;采用VCA和内摩阻角φ双重指标可以有效控制薄表层沥青混合料的粗集料配比设计;公称最大粒径为13. 2 mm(UTL-13)矿料级配三档集料含量的推荐范围分别为12. 5%～22. 2%,37. 5%～44. 4%,33. 3%～50%;UTL-10三档集料含量的推荐范围分别为10%～16. 7%,40%～50%,33. 3%～50%。更多还原

【Abstract】 This work aimed to explore the skeleton characteristics of thin-layer asphalt mixture and to ensure the aggregate gradation stability of UTL-10.We introduced 7. 5 mm sieve between 4. 75 mm and 9. 5 mm sieves,and carried out the dry-rodded test so as to analyze the voids in coarse aggregates(VCA) under different coarse aggregate contents. Meanwhile,we conducted uniaxial penetration test upon the coarse aggregate-asphalt mortar specimens,and thus the parameters related to shear strength of different coarse aggregate proportions were obtained. Consequently the indexes for the proportion control of coarse aggregate in ultra-thin asphalt mixture were determined,and the recommended ranges of coarse aggregates content were presented as well. The results indicated that the internal friction angle φ of coarse aggregate can be used to reflect the skeleton strength stability of coarse aggregate gradation. Meanwhile,by the combination of VCA and internal friction angle φ,the coarse aggregate proportion design of ultra-thin asphalt mixture can be effectively controlled. The UTL-13 recommended contents of the three coarse aggregate are 12. 5% —22. 2%,37. 5% —44. 4% and 33. 3% —50%,respectively. And the UTL-10 recommended contents of the three coarse aggregate are 10% —16. 7%,40% —50% and 33. 3% —50% respectively.更多还原