旧水泥混凝土路面沥青加铺层疲劳断裂分析

在道路的使用过程中,沥青加铺层一直经历着交通荷载及温度变化的循环作用,沥青加铺层结构中的裂缝扩展呈现为疲劳断裂特征.沥青加铺层的使用寿命（从开始承载直至破坏所经历的车辆荷载及温度循环次数或作用时间）可分为疲劳裂缝形成寿命和疲劳裂缝扩展寿命两部分.疲劳裂缝形成寿命为由微观缺陷发展到宏观可检裂缝所对应的寿命,目前仍由传统疲劳理论的方法确定;而疲劳裂缝扩展寿命则为由宏观可检裂缝扩展到临界裂缝而发生破坏这段区间的寿命,用疲劳断裂力学方法确定.论文着重对沥青混合料与沥青路面的疲劳断裂进行分析.

Fatigue Fracture of Asphalt Overlayer on Old Cement Concrete Pavement

Asphalt overlayer has been bearing the circulation of traffic loading and temperature variation, and its crack propagation presents as fatigue fi＇acture.The service life ofthe Asphalt overlayer （cycle index or action time oftraffic loading and temperature variation from start carry until damage） can be divided into two parts--the fatigue crack initiation life and fatigue crack propagation life .Fatigue crack initiation life is the corresponding life from the development of micro defects to macro detecting cracks, which is currently still determined by the traditional fatigue theory, and fatigue crack propagation life is the corresponding life from the development of macro detecting cracks to Critical Cracks ,which is determined by fatigue fracture mechanics method. This paper emphatically analyze the fatigue fracture of asphalt mixture and asphalt pavement.