基于分散技术的聚乙烯醇纤维沥青胶浆疲劳性能分析

为探究聚乙烯醇纤维（Polyvinyl alcohol fiber）分散后沥青胶浆的疲劳变化规律，探索性地采用旋转活塞式拌和法对PVA纤维沥青进行拌和分散，从PVA纤维的微观形貌出发，探究其纤维提高疲劳性能的原因。另外利用动态剪切仪（DSR）PVA纤维沥青进行时间疲劳扫描，通过复数模量衰减Nf50和累积耗散能比Nder对PVA纤维沥青胶浆疲劳性能进行评价。试验结果表明，PVA纤维表面有随机分布的凸起颗粒以及非完整光滑的表面，这种结构与沥青形成了很好的适配性，PVA纤维在沥青中起到了稳定、增粘、复合加筋作用，从而综合提高了沥青疲劳性能。同时，Nf50和Nder都能很好地评价沥青的疲劳性能，从物理表达清晰、易于确定、结构设计安全角度出发，更推荐采用累积耗散能比Nder指标用于评价沥青疲劳性能。

Study on fatigue properties of PVA fiber asphalt mortar based on dispersion technology

In order to investigate the fatigue behavior of asphalt mortar after the dispersion of polyvinyl alcohol fiber (PVA fiber), the rotating piston mixing method was used to mix and disperse the PVA fiber asphalt exploratively, and the microscopic morphology of PVA fiber was used to investigate the reason of its fiber to improve the fatigue performance. In addition, the fatigue performance of PVA fiber asphalt mastic were evaluated by the complex modulus decay Nf50 and cumulative dissipation energy ratio Nder using dynamic shear rheometer(DSR) for time scanning. The test results show that the PVA fiber surface have randomly distributed raised particles as well as non-complete smooth surface, and this structure forms a good adaptability with the asphalt, and the PVA fiber plays a stabilizing, viscosity increasing and composite reinforcing role in the asphalt, thus comprehensively improving the asphalt fatigue performance. At the same time, both Nf50 and Nder can evaluate the fatigue performance of asphalt well, it is more recommended to use the Nder index for evaluating the fatigue performance of asphalt from the perspective of clear physical expression, easy to determine, and structural design safety.