摘要
在路面结构性维修中铺设应力吸收层可减缓基层反射裂缝向上层扩展。为了提升路面结构的耐久性,充分发挥旧沥青路面铣刨料的循环利用价值,将路面铣刨料按多档筛分,将其中的细料部分应用于应力吸收层当中,并以稳定型橡胶沥青作为结合料,根据各档旧料的试验结果设计并制备了再生应力吸收层混合料。基于室内试验综合探究了橡胶沥青再生应力吸收层混合料的各项路用性能,分析了稳定型橡胶沥青及厂伴热再生技术在应力吸收层中的适用性。结果表明:基于稳定型橡胶沥青制备的热再生应力吸收层低温柔韧性较强,在35%的旧料掺量下,极限弯拉应变超过3 400με,且60℃动稳定度达到2 300次/mm以上,即使在50%的旧料掺量下,极限弯拉应变不低于2 800με,且60℃动稳定度超过2 600次/mm;根据含预切缝的半圆弯曲试验断裂韧度,稳定型橡胶沥青再生应力吸收层抗裂性能突出,随着旧料掺量的提高,其抗裂性能略有下降,在35%的旧料掺量下断裂韧度下降约8. 4%,在50%的旧料掺量下断裂韧度下降约18%。将旧料细料应用于应力吸收层可有效提升旧料的再生利用价值,降低应力吸收层建设成本,保障再生路面的长期使用性能。
Paving stress-absorbing layer can effectively reduce the reflection crack extending to upper layer in pavement structural maintenance.In order to improve the durability of pavement structure and explore the recycling value of reclaimed asphalt pavement (RAP)milling material,the multilevel screened fine fraction of pavement milling material is applied in stress absorbing layer,and the stable asphalt rubber is applied as the binder to design and prepare the recycled stress-absorbing layer material based on the test result of each fraction of RAP.The road performance of asphalt rubber recycled stress-absorbing layer material is evaluated by indoor test,and the applicability of stable asphalt rubber and hot in-plant recycling technology for stress- absorbing layer is analyzed.The result indicates that (1)The hot recycled stress-absorbing produced by stable asphalt rubber and RAP shows superior low-temperature flexibility.With 35%RAP content,the ultimate flexural-tensile strain is above 3400με,and the dynamic stability at 60℃2is more than 2300 times/ram.Even with 50%RAP content,the ultimate flexural-tensile strain is not less than 2800με,and the dynamic stability at 60℃ is above 2600times/mm.(2)According to the fracture toughness obtained by the notched semi-circular bending test,the recycled stress-absorbing laver with stable rubber performs well in crack resistance.The fracture resistance of recycled stress-absorbing layer material decreases slightly with the increase of RAP content,the fracture toughness decreased by 8.4%at 35%RAP content,and decreased by 18%at 50%RAP content.(3)The application of fine fraction of RAP in stress-absorbing layer can effectively enhance the recycling value of RAP,reduce the construction cost of stress-absorbing layer,and ensure the long-term performance of recycled pavement.
作者
祝谭雍
程其瑜
许兵
黄晓明
马涛
ZHU Tan-yong;CHENG Qi-yu;XU Bing;HUANG Xiao-ming;MA Tao(Jiangxi Expressway Maintenance Tecbalology Research Center,Nanchang Jiangxi 330025,China;Jiangxi Provincial Expressway Investment Group Co.,Ltd.,Jixnagxi Nanchang Jiangxi 330025,China;Southeast University,Nanjing Jiangsu 210096,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2018年第12期35-41,共7页
Journal of Highway and Transportation Research and Development
基金
国家自然科学基金项目(51378006
51378123)
江西省交通运输厅科技项目(2018Q0029)
关键词
道路工程
厂拌热再生
半圆弯曲试验
应力吸收层
稳定型橡胶沥青
road engineering
hot in-plant recycling
semi-circular bending test
stress-absorbing layer
stable asphalt rubber
