沥青结合料老化对路面功能层力学性能的影响

为考察沥青结合料老化对路面功能层力学性能的影响,运用Bisar和Ansys程序计算了不同老化程度的沥青路面的应力应变分布情况.通过计算分析可知:沥青层中产生的最大拉应力位于路表面双轮中心处;路面老化后,沥青层中产生的最大拉应力增加,最大拉应变与未老化路面相比,基本处于同一水平;在老化的前期(老化程度较轻时),沥青路面层内产生的最大剪应力远大于沥青路面层产生的最大拉应力;随着路面老化程度的加深,路面表面双轮中心处的拉应力(沥青层内产生的最大拉应力)接近甚至大于沥青面层的最大剪应力;这表明,路面在使用前期容易发生剪切破坏,随着路面老化程度的加深,路面更容易产生拉伸破坏.

Influence of asphalt binder aging on mechanical performance of pavement functional layer

To get the relationship between the pavement performance and the aging of asphalt binder at the different pavement temperature and depth, the strain and stress of the asphalt pavement is calculated and analyzed on the basis of Bisar and Ansys program. The conclusions are arrived at the largest tensile stress lies at the center of double tires of the different aging degree asphalt pavement surface. The largest tensile stress increases with the deeper aging degree of the asphalt pavement. However, the largest tensile strain of the aging asphalt pavement keep the same level as the new asphalt pavement. The mechanical analysis of aging asphalt pavement shows that in the asphalt pavement layer the largest shear stress is much larger than the largest tensile stress for a new pavement and the largest tensile stress is larger than or nearly equal to the largest shear stress for an aging pavement. This means the new asphalt pavement is apt to shear failure and the further aging asphalt pavement is apt to tensile failure.