摘要
青海地区紫外线辐射强、气温低、风速大等特殊自然条件容易引起沥青老化,导致沥青路面路用性能严重降低。为提高青海地区沥青路面抗老化性能,采用抗紫外线剂UV-531、抗剥落剂PA-1和低温性能提升剂SBR,通过沥青四组分试验并结合基本性能试验、低温弯曲梁流变试验和动态剪切流变试验,对沥青进行复合改性研究。结果表明:(1)改性剂的加入会引起沥青组分的变化,促使沥青的胶体结构更趋向于凝胶型,能提高沥青的抗老化性能;(2)以针入度作为评价依据,组分为0.7%PA-1+1.6%UV531+1.0%SBR(占基质沥青质量分数)的改性沥青F在未老化、短期老化和长期老化状态下,针入度分别提升了30.0%、42.5%和20.3%,沥青抗老化性能改善显著;(3)通过BBR试验,发现改性沥青F在3种老化状态下的S/m值平均降低-35.6%、-53.6%和-22.6%,沥青的低温性能得到提升;(4)通过DSR试验进行高温性能评价,发现改性沥青F抗车辙因子G*/sinδ远高于基质沥青,且老化对G*/sinδ影响逐渐变小,具有很好的高温稳定性。本试验研究表明,改性沥青F具有较好的抗老化性能,适合青海地区使用。
Asphalt aging can be caused by special natural conditions such as strong ultraviolet radiation,low temperature and high wind speed in Qinghai,which will result in severe degradation of pavement performance.Anti-ultraviolet agent UV-531,anti-stripping agent PA-1 and low-temperature performance enhancer SBR are used to improve the anti-aging performance of asphalt pavement in Qinghai.The composite modification of asphalt is studied through four component test of asphalt combining with basic performance test,low temperature bending beam rheology and dynamic shear rheology test.The results show that:(1)The addition of modifier will cause changes in the composition of asphalt,which will promote the gel structure of asphalt to tend to gel type and improve its aging resistance;(2)The penetration rate of modified asphalt F with 0.7%PA-1+1.6%UV531+1.0%SBR(mass fraction of matrix asphalt)increases by 30.0%,42.5%and 20.3%respectively under the condition of non-aging,short-term aging and long-term aging,indicating that aging resistance of asphalt is improved significantly;(3)It is found through BBR test that S/m value of modified asphalt F decreases by-35.6%,-53.6%,-22.6%on average under the three aging conditions,indicating that low-temperature performance of asphalt is improved;(4)Through the high temperature performance evaluation of DSR test,it is found that G*/sinδof modified asphalt F is much higher than that of matrix asphalt.The effect of aging on G*/sinδis gradually reduced with excellent high temperature stability.The research shows that the modified asphalt F has good anti-aging performance,which is applicable to Qinghai.
作者
闵天府
苏延桂
刘延金
MIN Tianfu;SU Yangui;LIU Yanjin(School of Civil Engineering,Qinghai University,Xining 810016,China)
出处
《青海大学学报》
2022年第3期76-84,共9页
Journal of Qinghai University
关键词
复配改性沥青
抗老化
低温性能
高温性能
流变特性
四组分试验
composite modified asphalt
anti-aging
low temperature performance
high temperature performance
rheological properties
four component test
