中、下面层沥青混合料疲劳性能研究

摘要

The paper aims to search for asphalt mixtures design method used in interface layer and underlying surface by comparison fatigue performance of 7 types asphalt mixtures used in interface layer and underlying surface. 7 types of asphalt mixtures are selected based on the test results of stability of high temperature, low temperature and water interiorly and overseas. The fatigue equations and fatigue life curves of 7 types asphalt mixtures for interface layer and underlying surface under different design method are gained by beam flexur-al fatigue test under stress control mode on MTS810. Weibull fatigue equations and its life curves of 50 or 90 percent warranty are gained. It is find that the anti-fatigue performance of gradation SAC20 is equal to gradation LAC20 by contrast to anti-fatigue performance of gradation in interface layer,and that anti-fatigue performance of gradation AC20 has evidence advantages than the other gradations. The good order of anti-fatigue performance is gradation SAC,LAC25,SUP25,AC25. The author recommends that high performance asphalt mixtures design schemes are selected for the use of interface layer and underlying surface by the contrast research of the fatigue performance to try to find out asphalt mixtures design method for the use of interface layer and underlying surface. The results show that gradation AC20 is suitable for interface layer and gradation SAC25 and LAC25 for underlying surface.%目的 研究7种类型中、下面层沥青混合料疲劳性能,探寻适合中、下面层使用的沥青混合料配合比设计方法.方法 通过高温、低温和水稳定性试验检测,筛选出7种类型的沥青混合料,在MTS810上采用应力控制模式进行小梁弯曲疲劳试验.结果 得到不同设计方法下7种类型中、下面层沥青混合料保证率分别为50％和90％的成布尔疲劳方程和疲劳寿命曲线.对中面层级配抗疲劳性能的对比分析,发现SAC20级配与LAC20级配抗疲劳性能基本相等,而AC20级配抗疲劳性能则明显优于其余两个级配.对下面层级配抗疲劳性能进行对比分析,抗疲劳性能优良顺序为SAC25级配、LAC25级配、SUP25级配、AC25级配.结论 笔者推荐适用于中面层的级配为AC20级配,适合应用于下面层的级配为SAC25级配、LAC25级配.