基于疲劳寿命的两类沥青路面再认识

Re-understanding of Two Types of Asphalt Pavement Based on Fatigue Life

半刚性基层沥青路面及复合式基层沥青路面最本质的区别在于路面破坏模式的不同。为了从理论上进一步阐明、印证这种区别,选取两类路面的典型结构,基于疲劳寿命理论,采用我国沥青路面设计方法中推荐的疲劳方程,分别以沥青层底拉应力及半刚性层底拉应力作为指标控制面层及基层的疲劳寿命,以此评价并比较面层及基层的相对寿命长短,从理论上揭示出两类沥青路面的破坏根源。结果表明：半刚性基层沥青路面的破坏源于半刚性基层,破坏模式属于自下而上;复合式基层沥青路面的破坏源于面层,破坏模式属于自上而下。

The essential difference between semi-rigid base asphalt pavement and compound base asphalt pavement is their different failure models.In order to deeply illustrate and corroborate the difference theoretically,based on fatigue life theory,two typical structures were chosen,using the fatigue equations recommended in Chinese asphalt pavement design method,taking the tension stress at bottom of asphalt layer and the tension stress at bottom of semi-rigid base as index to control fatigue life of asphalt surface and base,so the relative life of asphalt surface and base was evaluated and compared.Finally the failure root of two types of pavement was revealed theoretically.The results showed that failure started from base for semi-rigid base asphalt pavement and its failure model was from below,and failure started from asphalt surface for compound base asphalt pavement and its failure model was from top.