刚柔复合式路面反射裂缝扩展机理与防治措施研究

Research on Propagation Mechanism of Reflection Cracking on Rigid-reflexible Composite Pavement and Control Measures

对于水泥混凝土板上铺筑沥青混合料面层的刚柔复合路面结构,反射裂缝是其主要病害之一。通过数值分析来探讨刚柔复合路面结构反射开裂主要原因,并采用改进的车辙试验对不同防反射裂缝材料的抗裂效果进行分析。试验结果表明:裂缝处的应力集中是复合路面结构产生这类破坏的主要原因,其中,温度变化对裂缝处沥青混合料加铺层破坏作用最大,其次是车辆偏荷载作用,破坏作用最小的是车辆正荷载作用;铺设玻纤格栅的复合路面结构层其抗反射裂缝效果最好,其次是铺设聚酯玻纤布和玻璃纤维的增强应力吸收层(FR-SAMI),最差的是只涂SBS改性沥青粘层的复合路面。

For rigid - reflexible composite pavement structure of asphalt mixture surface course paved on cement concrete slabs, reflection cracking is one of main diseases. This paper probes into main reasons of reflection cracking on rigid -reflexible composite pavement structure via numeric analysis and analyzes the effect of anti - crack of different anti - reflection materials by means of improved rutting test. Test results show that stress concentration at cracks is main reason of such destroy produced in composite pavement structure, in which temperature change plays a role of maximum damage to pavement of asphalt mixture at cracks, followed by the effect of unbalanced load, and the effect of positive load shows the minimum damage ; the effect of anti - reflection cracks of composite pavement structural layer paved with glass fiber grids is the best, enhanced stress absorbing layer （FR -SAMI） paved with fiberglass -polyester paving mat and glass fiber is in the second place, and the effect of composite pavement only coated with SBS modified asphalt bonding layer is the worst.