旧路加宽沥青路面缓裂结构与材料研究

Research on Crack Retarding Structure and Material for Asphalt Pavement in Old Road Widening

摘要: 基于旧路加宽改造工程中普遍存在的由于新旧路基不均匀沉降变形引起的加宽路面纵向开裂问题，提出了利用土工布及应力吸收层提高路面结构抗裂性能的缓裂路面结构及相应结构材料，并通过小梁弯曲疲劳试验对各种抗裂结构的抗疲劳开裂性能进行研究。研究表明路基不均匀沉降对路面结构的抗疲劳开裂性能具有明显负面影响，加剧了路面结构的疲劳破坏过程；在沥青混合料下粘接土工布可以在一定程度上提高路面结构的抗开裂性能，而在此基础上加铺应力吸收层组成复合抗裂体系，可以使路面结构的抗开裂能力明显提高。

Abstract: Based on the universal problem in old road widening that the widened pavement longitudinally cracks caused by uneven settlement of the old and new subgrade, crack retarding structure and material for asphalt pavement using geotextile and stress absorption layer to enhance the crack resistance of pavement were proposed. The fatigue crack resistance of various structures was stu-died by trabeculae fatigue bending test. The study shows that there is obvious negative effect of the uneven settlement of subgrade on the fatigue crack resistance of pavement, which aggravates the fatigue failure process of pavement. Setting geotextile under asphalt mixture can improve the crack resistance of pavement structure certainly, while the crack resistance of pavement structure can be improved significantly by setting stress absorption layer based on the structure containing geotextile to form a composite anti-crack system.