摘要
为研究应用旧沥青路面材料冷再生基层的混合料力学性能,回收原沥青路面面层旧料和基层旧料,制备沥青路面全深式冷再生基层材料,结合现场沥青面层及铣刨深度测试冷再生材料级配,测试冷再生基层材料的7 d无侧限抗压强度、90d劈裂强度和90d回弹模量,并观察其SEM微观形貌图。结果表明：水泥用量较少时7d无侧限抗压强度、90d劈裂强度和90d回弹模量均随水泥剂量的增加快速增长,但是增长趋势逐渐变缓;较少的沥青旧料对再生基层力学性能是有利的,但是过多的沥青旧料则会产生较大的负面影响;当面层旧料的油石比较小时,水泥水化物取向结晶能刺破沥青膜层,直接与裹附在沥青内部的集料接触,形成较强的界面,这样能有效缓解沥青对强度的负面影响。进而建议低等级公路的中、轻型交通等级水泥剂量在5%-7%,其他类型公路则在提高水泥剂量的同时需要改善旧料级配;油石比小的旧沥青路面改造更适合推行全深式冷再生基层技术。
In order to analyze the mechanical properties of cold regenerated base mixture from old asphalt pavement,the old material of original asphalt pavement and base was recycled to prepare the full depth base mixture. Combined with on-site asphalt surface layer and milling depth,the gradation of cold regenerated base mixture was analyzed. The 7 d unconfined compressive strength,90d splitting strength and 90d modulus of resilience of the mixture were tested,and the SEM morphology of the mixture was observed. The results show that,when less amount of cement content was used,the 7 d unconfined compressive strength,90d splitting strength and 90d resilient modulus of the mixture increase rapidly with the growth of the cement dosage,while the growth is becoming slowly;that it would benefit the mechanical properties of reclaimed base if a small quantity of RAPs were used,but excessive RAPs would cause negative effect; that,when the asphalt proportion in the surface RAP is small,the orientation crystallization of cement hydrates can prick the asphalt film and contact directly with aggregate coated with the asphalt film,which forms strong interface,and the negative effect of asphalt on strength was mitigated. The amount of 5% - 7% cement by weight of the mixture is recommended for use in low grade and light traffic highways,and higher percentage of cement is recommended for other highways while the gradation of reclaimed aggregate should be improved. Asphalt pavement with lower oil stone ratio is more suitable to use the cold regenerated base.
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2016年第1期253-260,共8页
Journal of Guangxi University（Natural Science Edition）
基金
国家自然科学基金资助项目(51508030)
青海省重大科技专项计划项目(2014-GX-A2A)
青海省交通科技项目(2013-02)
关键词
沥青路面
配合比设计
冷再生基层
水泥稳定
asphalt pavement
mix design
cold regenerative base
cement stabilized
