摘要
基于砂沥青混合料蠕变特征,在Burgers模型中串联粘塑性体,并对粘塑性体中粘性系数进行改进,得到描述整个蠕变过程的非线性粘弹模型,理论推导和分析了模型蠕变方程.进行了砂沥青混合料试样施加不同应力下单轴压缩蠕变实验,由最小二乘法编制非线性拟合程序求得模型参数,拟合得到各模型参数与应力函数关系式.通过模型预测和实验值对比,结果表明,模型完整描述了砂沥青混合料蠕变过程3个阶段,尤其反映了加速蠕变的非线性粘弹特征.
A nonlinear viscoelastic model of sand asphalt mixtures that can reflect the total creep deformation stages is presented. Burgers model, which often describes the frontal two stages of creep deformation, is extended to a nonlinear model by combining a viscoplastic model in series; and the viscosity coefficient of viscoplastic model is modified. A creep representation equation of the model is established for the uniaxial loading condition. For the determination of model stress dependent parameters, uniaxial compression tests are performed under different stress levels. Moreover, expressions of the model parameters in terms of stress are also given. The resulting nonlinear viscoelastic model successfully predicts the experimental results of sand asphalt mixtures under various loading stress amplitudes.
出处
《三峡大学学报（自然科学版）》
CAS
2008年第4期36-38,51,共4页
Journal of China Three Gorges University：Natural Sciences
基金
国家自然科学基金资助项目(10672063)
