振荡剪切荷载下沥青非线性黏弹性研究综述

Review of Nonlinear Viscoelasticity of Asphalt Binders Under Oscillatory Shear Loading

沥青作为一种典型的黏弹材料,其黏弹性与路用性能密切相关,20世纪研究者们就开始关注并研究沥青的黏弹性。全面表征复杂条件下沥青的黏弹性,对于准确评价沥青路用性能具有重要的意义。实际应用中,沥青路面不可避免承受小幅及大幅振荡剪切荷载,沥青线性黏弹性与非线性黏弹性的研究同等重要,仅研究沥青线性黏弹性会导致沥青路用性能评价不准确。目前,基于稳态蠕变试验的沥青非线性黏弹性研究已基本成熟,但车辆对路面的实际作用模式为振荡剪切荷载,针对振荡剪切荷载下沥青非线性黏弹性的研究尤为重要。大幅振荡剪切试验是材料非线性黏弹性测试的主要方法,已成功应用于胶体、悬浮液等领域,而关于大幅振荡剪切荷载下沥青非线性黏弹性的研究则刚刚起步。为促进沥青非线性黏弹性的研究,综述了国内外大幅振荡剪切荷载下沥青非线性黏弹性的测试方法、分析方法及本构模型,指出了现有大幅振荡剪切荷载下沥青非线性黏弹性研究存在的问题,提出了未来沥青非线性黏弹性研究的建议。研究可为沥青非线性黏弹参数的确定、路用性能的评价及预测提供理论依据,同时为其他黏弹材料的非线性黏弹性研究提供一定参考。

As typical viscoelastic materials, asphalt binders possess viscoelastic properties that are closely related to their pavement performances. Comprehensively characterizing the viscoelasticity of asphalt binders under complex conditions is crucial to accurately evaluate the pavement performance of asphalt binders. Asphalt pavements are inevitably subjected to small and large oscillatory shear loads. Studying linear and nonlinear viscoelastic properties of asphalt binders are essential for pavement service. However, only the linear viscoelastic properties of asphalt binders have been studied, leading to the inability to evaluate asphalt pavement performances accurately. Researchers have focused on the nonlinear creep property of asphalt binders under steady loads;however, the actual loading action mode on road pavement is oscillatory shear load. Thus, studying nonlinear viscoelasticity for asphalt binder under oscillatory shear load is more important. The large amplitude oscillatory shear(LAOS) test is an important measurement method to obtain the nonlinear rheological characteristics of materials. Although LAOS has been extensively applied to colloid suspensions, research concerning the nonlinearity of asphalt binders under LAOS has been in the initial stages. This paper presents a review of the test and analysis methods and constitutive models of nonlinear viscoelasticity for asphalt binders under LAOS. The existing problems in studying the nonlinear viscoelasticity of asphalt binders are identified, and suggestions to deepen the studies are proposed. Thus, this paper affords a solid theoretical foundation for accurately evaluating and predicting asphalt pavement performances. It can also provide a basis and reference for studying the nonlinear viscoelasticity of other rheological materials.