不同标号沥青对心墙沥青混凝土弯曲性能的影响

Influence of Asphalt Grade on Flexural Performance of Asphalt Concrete as an Impervious Core in Embankment Dam

沥青作为沥青混凝土的重要组成部分,无论是沥青自身质量性质还是其在沥青混凝土中的含量,对心墙沥青混凝土的性能有很大影响。通过小梁弯曲试验,研究了克拉玛依50~#,70~#,90~#,110~#,160~#沥青对心墙沥青混凝土弯曲性能的影响。试验结果表明:沥青混凝土抗弯强度对应的应变随着沥青标号的增大而增大,沥青标号的提高有助于沥青混凝土变形能力的提高,但会使抗弯强度与模量降低;沥青标号对沥青混凝土强度的影响随着沥青标号的升高而减小,高标号沥青对于心墙沥青混凝土强度影响变幅不大,在强度满足要求的情况下,应优先考虑高标号沥青。研究结果可为沥青混凝土心墙沥青标号的选择提供参考。

As an important composition of asphalt concrete,asphalt in terms of quality and content has great influence on the performance of core wall. The effect of Karamay asphalt of different grades( 50~#,70~#,90~#,110~#,and 160~#) on the performance of asphalt concrete is studied through bending test of small beam. Results reveal that the strain corresponding to flexural strength of asphalt concrete increases with the increase of asphalt grade,which suggest that increasing asphalt grade is conducive to improving the deformation resistance of asphalt concrete but is unfavorable to the bending strength and modulus. This effect weakens with the increase of asphalt grade. Therefore we recommend to selecting high grade asphalt as a priority when strength meets requirements. The research results offer reference for the selection of asphalt grade in asphalt concrete core wall.