用车辙系数评价沥青混合料的抗车辙性能

Evaluation of Anti-Wheel-Rutting Performance of Asphalt Mixture by Using Wheel-Rutting Index

提出了车辙系数(WR I)指标这一概念,综合考虑了行车速率、累积变形量和最大永久变形量等因素对压实沥青混合料高温性能的影响,对不同时间车辙发生的程度进行了对比、分析.结果表明:动稳定度指标缺乏对全过程的累积变形量和最大永久变形量的考虑,在评价沥青混合料的高温性能时存在较大的局限性,车辙系数指标能较好体现工程实际中车辙的形成规律,有效避免高温性能差别明显而动稳定度基本一致的不合理情况,提高了对沥青混合料高温性能评价的区分率.

Wheel-rutting index （ WRI）, a new index for evaluating the whole-term high-temperature stability of as phalt mixture is presented by taking into account all the factors affecting the high-temperature performance, such as the velocity, the cumulate deformation and the maximal permanent deformation, and the analysis and comparison of the degrees of track ruts in different periods are then carried out. The results show that the index of DS is not satisfactory because it overlooks the maximum deformation and the maximal permanent deformation in the whole process. Thus, it is quite limited in use in the evaluation of the high-temperature performance of asphalt mixture. On the contrary, WRI accords well with the regular patterning of rut formation in practice, and that it shows an effective distinction in the evaluation of the high-temperature stability, without causing the unreasonable occurrence in which the high-temperature performances are obviously different while the dynamic stabilities remain similar.