重复荷载下沥青混合料变形的粘弹性有限元分析

沥青混合料是典型的粘弹性材料，广义Maxwell粘弹模型能很好地描述沥青混合料的变形规律。通过拟合AC-13C基质、改性沥青混合料的静载蠕变试验数据获得广义Maxwell模型的Prony系列系数，采用加载0.1s、卸载0.9s的半正弦波间歇荷载模拟路面实际的车辆荷载，对重复荷载作用下的沥青混合料进行粘弹性有限元分析，预测出重复荷载作用下AC-13C基质、沥青混合料的变形，与实测变形相比具有很好的一致性。粘弹性有限元方法预测出的应变包括弹性应变和蠕变应变，而蠕变应变直接导致永久变形的产生，通过分析蠕变应变可以判别沥青混合料的弹性恢复能力。

Viscoelastic Finite Element Analysis on the Deformation of Asphalt Mixtures under Repeated Load

Asphalt mixture is a typical viscoelastic material, the deformation of asphalt mixtures can be well described by the Generalized maxwell viscoelastic mechanical model. The prony series coefficients of the Generalized Maxwell model are obtained from static creep test of AC-13C unmodified and modified asphalt mixtures, a half-sinusoids load with 0.1s loading duration and 0.9s unloading duration is used to simulate the dynamic vehicle load, and the strain of AC-13C unmodified and modified asphalt mixtures under repeated loads is analysed by viscoelastic finite element method, then we obtain an excellent correlation with the measured strain. The predicted strain via viscoelastic finite element method includes elastic strain and creep strain, and the creep strain will lead to permanent deformation, so that the elastic resilience of asphalt mixtures could be determined by analyzing the creep strain.