在40℃下进行了5种不同应力水平下的沥青砂单轴压缩蠕变实验,分别采用三参数固体、三参数流体、四参数固体、四参数流体和指数模型5种不同模型刻画沥青砂的单轴蠕变特征,根据最小二乘原理拟合模型参数,然后进行对比分析.结果表明:四参数流体模型拟合结果与实验值符合最好,更适合于描述沥青砂蠕变特性,其次为三参数固体模型.5种模型均反映了沥青砂试样的第二蠕变特征,四参数流体与三参数固体模型还能描述沥青砂的初始蠕变特征,而指数模型能反映沥青砂试样的第三蠕变特征.
The uniaxial creep experiments ducted at 40 ℃. In order to describe the of asphalt sand samples under five different stresses are concreep properties of asphalt san three parameters solid, three parameters liquid, four parameters solid, the viscoelastic model i. e. our parameters liquid, and exponential model are adopted. On basis of least squares techniques, the nonlinear fitting proceduce can be used to analysis creep properties of these models. The study shows the four parameters liquid model may have optimal characterize creep curve of asphalt sand samples, secondly is the three parameters solid model. Five models show good agreement with the second creep course of asphalt sand samples. Further more, four parameters liquid and three parameters solid models can predict the characteristics of the first creep course, while exponential model is found to agree well with the third course of creep curve.