Abstract: In order to clarify the nature of the excellent high and low temperature road performance of composite concrete and to guide the design of composite concrete pavement, the viscoelastic properties of composite concrete in the general temperature range were studied. Three representative values of void ratio of composite concrete were selected — 22%, 25%, 28%. Based on dynamic modulus test, bending creep test and uniaxial compression creep test, the influece of the void ratio of matrix asphalt mixture on the viscoelastic properties of concrete was investigated. The reswarch results show that the viscoelastic properties of composite concrete are closely related with the void ratio of the matrix mixture. Under low temperature conditions, VV=25% composite concrete has relatively strong viscous characteristics. With the increase of temperature, the viscoelastic properties of composite concrete under three kinds of void ratios are gradually approaching. Under high temperature conditions, the viscous characteristics of composite concrete decrease as the void ratios increase. Therefore, compared with the composite concrete with 22% and 28% void ratio, the composite concrete with 25% void ratio has good high temperature stability and low temperature crack resistance. The research results provide a useful reference for the selection of material composition and the selection of design parameters for composite concrete design.

Key words: highway engineering, composite concrete, viscoelasticity, void ratio, dynamic modulus, bending creep, uniaxial compression creep

摘要： 为了明确复合混凝土优良高低温路用性能的本质并指导复合混凝土路面设计，对复合混凝土在一般温度域范围内的黏弹力学性能进行研究。选择复合混凝土空隙率范围的3种代表值(22%、25%、28%)，基于动态模量试验、弯曲蠕变试验和单轴压缩蠕变试验，探究基体沥青混合料空隙率对复合混凝土黏弹特性的影响。研究结果表明：复合混凝土的黏弹性能与基体混合料的空隙率关系密切，在低温条件下，VV=25%的复合混凝土具有相对较强的黏性特征；随着温度的升高，3种空隙率下的复合混凝土黏弹性能逐渐接近；到高温条件下，复合混凝土的黏性特征随空隙率的增大而减小。故相比于22%、28%空隙率的复合混凝土，25%空隙率复合混凝土同时具有较好的高温稳定性与低温抗裂性能。研究结果为复合混凝土设计时材料组成的选择和设计参数的选取提供参考。

关键词: 道路工程, 复合混凝土, 黏弹性, 空隙率, 动态模量, 弯曲蠕变, 单轴压缩蠕变