橡胶混凝土路用性能演变规律及作用机理研究

Study on the Evolution Law and Action Mechanism of Rubber Concrete Pavement Performance

针对传统橡胶混凝土宏观路用性能演化规律及协同增效机理不明等问题,研究了橡胶材料对混凝土的工作性能、力学强度和疲劳特性的影响,并从材料结构特性出发,探讨了橡胶混凝土的结合机理和界面疲劳损伤模型。研究结果表明:橡胶与水泥具有较强的交互特性,可通过中心碳原子的电子供给体特性与水泥基体形成H键,从而改善橡胶混凝土的流动性能。当橡胶掺量<15%时,制备的橡胶混凝土满足2000万次累计轴载作用次数的重交通荷载,服役寿命增延效果明显。此外,研究结果表明橡胶材料的粒径大小与橡胶混凝土的服役行为相关性强,粒径较小的橡胶粉与水泥间形成的ITZ较为稳定,具有良好的力学行为特征。

Aiming at the problem that the evolution law of macroscopic road performance and synergistic effect mechanism of traditional rubber concrete are not clear,the influence of rubber material on working performance,mechanical strength and fatigue characteristics of concrete was studied,and the bonding mechanism and interface fatigue damage model of rubber concrete were discussed based on the material structure characteristics.The results showed that the rubber and cement have strong interaction characteristics,which can form H bond with the cement matrix through the electron donor characteristics of the central carbon atom,so as to improve the flow performance of rubber concrete.When the rubber content is less than 15%,the prepared rubber concrete can meet the heavy traffic load of 20 million times of cumulative axial load,and the effect of prolonging the service life is obvious.In addition,the results show that the particle size of rubber material has a strong correlation with the service behavior of rubber concrete.ITZ formed between rubber powder with smaller particle size and cement is more stable and has good mechanical behavior characteristics.