沥青混合料高温性能评价指标区分度研究

High Temperature Performance Evaluation Indices of Asphalt Mixtures

针对中国沥青路面结构设计规范中的车辙试验和单轴贯入试验,实测得到9种沥青混合料的永久变形量、动稳定度、贯入强度和贯入位移4项指标,并进行4项指标的高温性能区分能力研究.首先利用箱型图定性比较同一指标对不同沥青混合料高温性能的区分能力;然后引入2种区分度计算方法——熵值赋权法和高低分组法,计算得到4项指标的区分度.结果表明:4项指标对应的沥青混合料高温性能区分能力存在显著差别;采用2种区分度计算方法得到的4项指标区分度排序一致,从高到低依次为永久变形量、贯入强度、贯入位移和动稳定度.建议沥青路面结构抗车辙设计时考虑不同指标的区分度,而车辙试验采用永久变形量代替动稳定度.

Aiming to the rutting test and uniaxial penetration test in the specifications for design of highway asphalt pavement in China,the distinguishing ability of high temperature performance of the corresponding test indexes was studied.The permanent deformation,dynamic stability,penetration strength and penetration displacement of 9 kinds of asphalt mixtures were measured in laboratory.The distinguishing ability of each index on the high temperature performance of different asphalt mixtures was qualitatively compared by the box diagram method.Then,two kinds of discrimination calculation methods,namely the entropy weighting method and the high⁃low grouping method,were introduced to calculate the discrimination of the four indices.The results show that:the four indices have significantly different distinguishing ability on the high temperature performance of asphalt mixtures;the four indices obtained by the two methods are in the same order,and the sequence from high to low is permanent deformation,penetration strength,penetration displacement and dynamic stability.It is suggested that the testing index differentiation should be considered for pavement anti⁃rutting design,and permanent deformation should be introduced instead of dynamic stability in the rutting test.