基于细观力学的纤维沥青混凝土有效松弛模量

为了研究纤维沥青混凝土的本构模型,将其视为以沥青混合料为粘弹性基体,纤维为弹性夹杂的两相复合材料。对基于复合材料细观力学理论建立的有效模量表达式进行了修正,提出了纤维沥青混凝土的割线有效松弛模量。以聚酯纤维沥青混凝土为例进行了有效松弛模量的解析分析和模拟蠕变实验的有限元分析,分析结果与试验数据的比较表明,该文提出的割线有效松弛模量模型对于纤维沥青混凝土粘弹性力学行为具有很好的预测能力。应用该模型对路面弯沉变形进行了有限元分析,结果表明:纤维的加入有效的改善了沥青混凝土路面的粘弹性性能。

EFFECTIVE RELAXATION MODULI OF FIBER REINFORCED ASPHALT CONCRETE BASED ON MICROMECHANICS

To study the constitutive property, fiber reinforced asphalt concrete is considered as a two-phase composite material. It contains asphalt concrete as the viscoelastic matrix, and fibers as the elastic inclusions. Based on the micromechanical model of effective moduli for composite materials, the secant effective relaxation moduli of fiber reinforced asphalt concrete are established. Using the new model, this paper analyzes the effective moduli of polymer fiber reinforced asphalt concrete theoretically. To make a comparison, the FE simulation of the concrete behavior considering creep effect is also performed. It is demonstrated that the present model can satisfactorily describe the viscoelastic behavior of fiber reinforced asphalt concrete. Finally, a FE analysis of pavement deflection is conducted by using the present constitutive model, showing that the intermingle of polymer fibers in asphalt concrete improves efficiently viscelastic property of pavements.