摘要
本研究利用70号道路石油沥青和SBS改性沥青,将温拌剂(Sasobit)、氢氧化铝(ATH)和有机蒙脱土(OMMT)与沥青复配,制备成三种不同阻燃剂掺量(质量分数)的温拌阻燃沥青,采用多应力蠕变恢复(MSCR)试验开展对温拌阻燃沥青高温性能的评价。分别对温拌阻燃沥青在60℃下的应变变化、蠕变恢复率(R)、不可恢复蠕变柔量(J_(nr))及其相应应力敏感性指标(R_(diff)、J_(nrdiff))进行分析,并依据AASHTO M 332-20标准对不同阻燃剂掺量的温拌阻燃沥青进行交通分级。结果表明:随着阻燃剂掺量的提高,两种类型沥青的应变值减小,J_(nr)值呈减小趋势,R值呈增大趋势;阻燃剂掺量较低时,提高其掺量对沥青结合料的高温性能改善效果更加明显;温拌阻燃沥青(道路石油沥青)的J_(nr3.2)值不满足AASHTO标准中“≤4.5”的要求。温拌阻燃沥青的J_(nrdiff)值均能满足AASHTO标准中“≤75%”的要求。温拌阻燃沥青(道路石油沥青)未达到标准交通要求而无法分级,温拌阻燃沥青(SBS改性沥青)在4%阻燃剂掺量下达到特重交通的标准,在8%、12%掺量下达到极重交通的标准,因此温拌阻燃沥青(SBS改性沥青)的高温性能更好。基于对温拌阻燃沥青蠕变力学指标、高温交通分级和经济性的综合考虑,推荐复配阻燃剂(ATH、OMMT的质量比为3∶1)的最佳掺量为8%。
In order to study the high temperature performance of warm-mixed flame retardant asphalt,the warm agents(Sasobit),aluminum hydroxide(ATH)and organic montmorillonite(OMMT)were added respectively into 70~#petroleum asphalt and SBS modified asphalt to prepare warm-mixed flame retardant asphalt with three kinds of different use levels(by mass).The high temperature performance of warm-mixed flame retar-dant asphalt was evaluated by multi-stress creep recovery(MSCR)test at 60℃.Then,strain variation percent recovery(R),non-recoverable creep compliance(J_(nr))and their stress sensitivity index(R_(diff),J_(nrdiff))derived from this test were analyzed.According to AASHTO M 332-20 specification,traffic grading was conducted on modified asphalt with different use levels of flame retardant.The results show that for the two types of asphalt,with the increase of use level of flame retardant,the strain decreases,the non-recoverable creep compliance shows downward trend and percent recovery shows upward trend,especially for flame retardant at lower content,which indicates that the increasing use level of flame retardant is more prominent for the improvement of high temperature performance of asphalt at lower flame retardant content.The J_(nr3.2)value of warm mix flame retardant bitumen(road petroleum bitumen)does not meet the requirement of‘≤4.5'in the AASHTO standard.The J_(nrdiff)values of warm mix flame retardant asphalt can meet the requirement of‘≤75%'in the AASHTO standard.Warm-mixed flame retardant asphalt(road petroleum asphalt)does not meet the requirements of standard traffic and thus can not be graded,warm-mixed flame retardant asphalt(SBS modified asphalt)reaches the standard of Very Heavy Traffic‘V'Grade at 4%flame retardant content,and Extremely Heavy Traffic‘E'Grade at 8%and 12%content,so warm mixed flame retardant asphalt(SBS modified asphalt)has better high temperature performance.Through comprehensive evaluation of various creep mechanical properties indicators,high temperature performance grade and traffic classification and economy,the optimal dosage of compound flame retardant is recommended to be 8%.
作者
刘圣洁
林钰
李梦然
周胜波
LIU Shengjie;LIN Yu;LI Mengran;ZHOU Shengbo(College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China;China Design Group,Nanjing 210014,China;Guangxi Jiaotou Technology Co.,Ltd.,Nanning 530000,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2023年第9期142-147,共6页
Materials Reports
基金
国家自然科学基金(51908194)
广西重点研发计划项目(AB20297033,AB17292032)
江西省重点研发项目(20192BBG70080)
中国博士后科学基金项目(2019M650101)
中央高校基本科研业务费项目(B200202071)。
