大碎石沥青混合料柔性基层在路面补强中的应用研究

Study of the use of large-stone asphalt mixes in the flexible base courses to reinforce pavements

将空隙率较高的最大粒径为37.5cm的大粒径沥青碎石混合料铺筑在老沥青路面上代替半刚性基层,解决半刚性基层补强中反射裂缝及排水问题。采用集料嵌挤方法进行级配设计,使用高粘度沥青增加沥青膜厚度,以析漏指标确定沥青用量,通过试验路提出大碎石沥青混合料柔性基层的施工工艺。试验路观测表明:大碎石沥青混合料柔性基层用于旧路改造,能够满足道路结构强度及高温稳定性要求,起到路面结构排水的作用,有效地防止了反射裂缝的产生。

Approach to strengthening old pavement structure that paves high void asphalt macadam with top-size aggregate 37.5 cm on existed pavement instead of semi-rigid base,can prevent base reflection cracking and drain water from base layer.This mix must be used high viscous asphalt to increase asphalt membrane thickness.The mix design is based on aggregate inter-lock method and use leakage test to determine asphalt content.Construction technique used asphalt macadam as flexible base layer is concluded through field test road.Field data demonstrates that this mix used as flexible base in pavement reconstruction can satisfy pavement strength,high-temperature stability requirements,drain water and prevents reflection cracking effectively.