“再生-改性”沥青性能研究

Study on the Performance of Recycled-Modified Asphalt

目的研究在再生剂和不同掺量改性剂作用下取得的"再生-改性"沥青的性能,为沥青路面再生-改性技术提供试验和理论依据.方法采用两种再生方案对老化沥青进行再生处理,对再生后的沥青进行针入度、软化点、延度、布氏黏度、动态剪切流变和弯曲梁流变等系列试验.结果采用添加再生剂方案再生的沥青其针入度、软化点、延度、车辙因子、临界温度、主曲线、劲度模量和蠕变速率与原样沥青非常接近;采用再生剂加改性剂的再生-改性方案可显著提升沥青的高温抗车辙和低温抗开裂的能力,且随着改性剂掺量的增加"再生-改性"沥青的高低温性能均逐渐增强.结论采用单一添加再生剂的普通再生方案可恢复沥青的高低温性能,采用再生-改性方案再生后沥青的高低温性能均显著优于原样沥青和普通再生沥青.

The purpose of this paper is to study the performance of recycled-modified asphalt under rejuvenating agent and different contents of modifiers,and to provide a experimental and theoretical basis for asphalt pavement recycling and modification technology.The aged asphalt was recovered by two recycling schemes,and the three indexes of bitumen,Brookfield viscosity,dynamic shear rheology and bending beam rheology tests were performed on the recycled asphalt samples.The results indicated that the three indexes of bitumen,rutting resistance,critical temperature,master curves,stiffness and creep rate of the asphalt binder recovered by the rejuvenating agent were very close to those of the original asphalt.The performance of the high temperature rutting resistance and low temperature anti-cracking of the asphalt binders can be significantly improved through the scheme of adding the rejuvenating agent and modifier.Moreover,the high and low temperature performance of recycled-modified asphalt was enhanced with the increase of the modifier content.The conclusion is that the high and low temperature performance of asphalt can be restored by adopting the scheme of solely adding rejuvenating agent,while the high and low temperature performance of asphalt that regenerated by the recycled and modified scheme are significantly better than that of the original asphalt and asphalt recoverd by the rejuvenating agent.