基于弯曲梁流变试验和黏弹性理论评价沥青低温性能研究  

Research on evaluation of asphalt low temperature performance based on rheological test of curved beam and viscoelastic theory

作　　者：银花[1,2] 李凯 YIN Hua;LI Kai(Transportation Institute of Inner Mongolia University,Hohhot 010070,China;Bridge Inspection and Maintenance and Reinforcement Engineering Technology Research Center,Inner Mongolia University,Hohhot 01007,China)

机构地区：[1]内蒙古大学交通学院,呼和浩特010070 [2]内蒙古大学桥梁检测与维修加固工程技术研究中心,呼和浩特010070

出　　处：《功能材料》2021年第10期10157-10165,共9页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(11562013);内蒙古自然科学基金资助项目(2020MS01013);内蒙古交通科技资助项目(222000-5206034)。

摘　　要：通过对长期老化状态下的90#基质沥青、SBS改性沥青、极寒沥青和橡胶沥青在不同低温(-12,-18,-24和-30℃)条件下进行低温弯曲梁流变(BBR)试验,分析了4种沥青60 s时的蠕变劲度模量S和蠕变速率m随温度的变化规律;基于分数阶微分理论,证明了黏弹性材料的黏弹性行为分数阶演算,并采用分数阶导数黏弹性模型对沥青BBR蠕变劲度曲线进行拟合,确定了相关的模型参数和物理意义。同时,基于分数阶导数黏弹性模型构建了沥青低温蠕变劲度模量S和蠕变速率m之间的物理方程。结果表明,BBR试验了4种沥青60 s时的蠕变劲度模量S和蠕变速率m与温度的关系,由于沥青会发生玻璃化转变,在温度低于-18℃时,其4种沥青的蠕变劲度模量S和蠕变速率m往往会发生突变,不会呈现显著的线性变化;分数阶导数黏弹性模型能够更加精确地描述BBR试验中的沥青低温性能,模型参数A和分数阶导数阶次α具有物理意义。参数A表示沥青低温变形因子,参数A值越大4种沥青的低温抗裂性越好;分数阶导数阶次α表示沥青低温松弛因子,α值越大,4种沥青的沥青低温松弛能力越强,分数阶导数阶次α可较好地预估沥青的低温蠕变速率m;基于分数阶导数黏弹性模型,沥青低温蠕变劲度模量S和蠕变速率m之间的物理方程可以采用蠕变柔量速率J′(t)表征,并通过增大模型参数分数阶导数阶次α,可以得到更大的蠕变柔量速率J′(t),以提高沥青低温抗裂性能,故蠕变柔量速率J′(t)是一种能够很好地表征沥青低温性能的指标。Through the long-term aging state of 90#matrix asphalt,SBS modified asphalt,extreme cold asphalt,rubber asphalt,low temperature bending beam flow under different low temperature(-12,-18,-24 and-30℃)conditions(BBR)test,analyzes the creep stiffness modulus and creep rate of 4 kinds of asphalts at 60 s with temperature;based on the fractional differential theory,it proves the fractional calculus of viscoelastic behavior of viscoelastic materials,and the fractional derivative viscoelastic model is used to fit the asphalt BBR creep stiffness curve,and the relevant model parameters and physical meaning are determined.At the same time,a physical equation between the low-temperature creep stiffness modulus S and creep rate m of the asphalt is constructed based on the fractional derivative viscoelastic model.The results show that the BBR tests the relationship between the creep stiffness modulus S and the creep rate m of the four asphalts at 60 s.As the asphalt undergoes glass transition,when the temperature is lower than-18℃,the four asphalts the creep stiffness modulus S and creep rate m often change abruptly and do not show a significant linear change;the fractional derivative viscoelastic model can more accurately describe the low-temperature performance of asphalt in BBR tests.Model parameters A andαfractional derivative order has physical meaning.A is the low-temperature deformation factor of asphalt.The larger the parameter A,the better the low-temperature crack resistance of the four asphalts.The larger the value of the parameter fractional derivative orderα,the stronger the low-temperature relaxation ability of the 4 types of asphalt,the fractional derivative order.The secondαis the low-temperature relaxation factor of the asphalt,and the fractional derivative order can well estimate the low-temperature creep rate of the asphalt;based on the fractional derivative viscoelastic model,the asphalt low-temperature creep stiffness modulus S and creep rate m the physical equations between them can be characterize

关 键 词：黏弹性模型 分数阶导数模型 弯曲梁流变(BBR)试验 沥青 低温性能 

分 类 号：TB332[一般工业技术—材料科学与工程] U414[交通运输工程—道路与铁道工程]