基于单轴压缩蠕变试验求解沥青混合料松弛模量

摘要

为了更加精确、方便地获得沥青混合料的松弛模量,对处于线性粘弹性状态的沥青混合料试件进行单轴压缩蠕变试验,根据蠕变柔量和松弛模量在拉普拉斯域内的转换关系,通过测得的蠕变柔量计算得到沥青混合料的松弛模量.结果表明,沥青混合料蠕变柔量和松弛模量的相互转换建立在线性粘弹性基础上,实现蠕变柔量向松弛模量的转化本质上是实现广义开尔文模型向广义麦克斯韦尔模型的转化.所提出的方法可用于以松弛模量为基础的沥青混合料粘弹性本构模型中,用于预测沥青路面的粘弹性响应.%In order to obtain the relaxation modulus conveniently and accurately, a material testing system (MTS) is employed to perform uniaxial compressive creep test on asphalt mixture specimens within the linear viscoelastic range. The measured creep compliance is converted into relaxation modulus in accordance with the interrelationship between creep compliance and relaxation modulus in the Laplace domain. Conclusions can be drawn that the interconversion between the creep compliance and relaxation modulus is based on the linear viscoelasticity and converting the creep compliance into relaxation modulus is essentially converting the Generalized Kelvin model into the Generalized Maxwell model. The conversion method proposed in this study can be extensively applied to various viscoelastic constitutive models that are based on the relaxation modulus so as to predict the viscoelastic responses of asphalt pavements.