高黏弹沥青砂蠕变损伤模型

Creep Damage Model of High Viscoelastic Asphalt Sand Mixture

应用Kachanov损伤模型表征沥青砂损伤的增长变化律,将Burgers模型与损伤因子进行耦合,构建出能够描述高黏弹沥青砂3阶段蠕变全过程的蠕变损伤模型.借助高黏弹沥青砂的弯曲蠕变试验数据,利用最小二乘法,得到相关模型系数和蠕变损伤演化曲线.将此蠕变损伤模型曲线与试验结果及Burgers模型曲线进行对比研究.结果表明:该蠕变损伤模型能准确描述高黏弹沥青砂的蠕变3阶段特性,拟合相关系数达到0.998.

Kachanov damage model was used to describe the growth rate of damage. Coupled with the Bur- gers model, the model parameters and the creep damage curve were obtained through the high viscoelastic bending creep tests with least square method. The comparison among the Burgers model, creep test and creep damage model was studied. The results indicate that the new creep damage model for the high visco- elastic asphalt sand mixture can describe accurately three stages of creep performance, fitting correlation coefficient is 0. 998.