纤维沥青混凝土FRA黏弹性预测模型

纤维沥青混凝土FRA(Fiber reinforced asphalt concrete)的力学行为取决于沥青混合料和纤维的物理属性及几何特征。通过三参数固体模型,考虑纤维的几何特性,构造了一种预测FRA黏弹性行为模型,推导出该模型的本构方程、蠕变柔量和松弛模量表达式。采用该模型研究了纤维体积分、比半径和弹性模量等对FRA松弛模量和蠕变柔量的影响。结果表明,纤维掺入量和比半径对FRA的松弛模量和蠕变柔量影响较大,而弹性模量影响较小。通过试验,验证了FRA预测模型具有较高的精度。在研究试验范围内,SMA-13沥青混凝土的聚丙烯腈纤维(PAN)最佳掺入量和长径比分别为0.3%～0.4%和600～900。

Viscoelastic prediction model of fiber reinforced asphalt concrete-FRA

The mechanical behavior of fiber reinforced asphalt concrete (FRA) depends on the physical and geometrical characteristics of the asphalt mixture and the fiber.Considering the geometric characteristics of the fiber,a model for predicting the viscoelastic behavior of FRA was constructed through the three parameter solid model.Using this model,the effects of fiber volume integral,specific radius and elastic modulus on FRA relaxation modulus and creep compliance were investigated.The results show that the fiber''s content and specific radius have a great influence on the relaxation modulus and creep compliance of FRA while the fiber''s elasticity modulus has less affect on them.Through experiments,it was proved that the FRA prediction model has a high precision.Based on the experimental and theoretical study in this paper,the optimum blending ratio and length diameter ratio of polypropylene fiber (PAN) for SMA-13 asphalt concrete are found to be 0.3%~0.4% and 600~900 respectively.