全厚式沥青面层车辙控制标准探讨

摘要

Rut control standards have been set only for bituminous mixtures, and thus unable to directly reflect asphalt surface structural anti-rut performance. The standard rut testing instrument was improved by allowing the speed of the test wheel adjustable. Laboratory rut tests were carried out under heavy loading and low speed condition using the improved rut testing instrument for single layer rut samples and total-thickness rut samples. An equation was employed for calculating total-thickness rut sample dynamic stability, with the coefficients obtained through regression of the rut test results. The variation of total-thickness sample dynamic stability with its component layers was analyzed using the regression equation, and the results showed that the top layer significantly influences total-thickness rut sample dynamic stability. The rut deformation structural contribution ratio of the component layers was also calculated to show that the middle layer was the greatest contributor to the total rut deformation. Total-thickness sample dynamic stability control standards were calculated using the regression equation when its component layers dynamic stability set to the standard values recommended in the specifications. The total-thickness sample dynamic stability control standard was employed to verify the anti-rut performance of a steep upgrade section asphalt surface and to explain the rut disease found in the section.%目前的研究都只针对沥青混合料提出材料的抗车辙控制标准，并不能直观地反映路面结构抗车辙性能。为此改进了车辙试验机，并在重载低速下开展多种沥青面层组合结构的全厚式车辙试验和各层沥青混合料的车辙试验；分析全厚式车辙动稳定度的构成，构造由各层沥青混合料动稳定度推算全厚式车辙动稳定度的公式；按照该公式对重载低速车辙试验数据进行回归，利用该回归方程分析沥青面层各层对全厚式车辙动稳定度的影响及其对车辙变形的结构贡献率，结果表明中面层对车辙变形的贡献率最大（与已有的研究结论一致），而上面层对全厚式车辙动稳定度的影响最大；基于各层沥青混合料的动稳定度控制标准，利用该回归方程提出全厚式车辙动稳定度控制标准；将该标准用于检验某高速公路长大上坡沥青路面抗车辙性能，能很好地解释其反复出现的车辙现象。