Yan Xin, Zhou Zhigang, Fang Yingjia, Ma Chongsen, Yu Guangtao
School of Traffic & Transportation Engineering, Changsha University of Science and Technology, Changsha 410114, China.
National Key Laboratory of Green and Long-Life Road Engineering in Extreme Environment, Changsha University of Science and Technology, Changsha 410114, China.
Materials (Basel). 2024 Oct 10;17(20):4942. doi: 10.3390/ma17204942.
To investigate the effect of hot and humid environmental factors on the mechanical properties of asphalt mixtures research, in this paper, the dynamic modulus of asphalt mixtures under the effects of aging, dry-wet cycling, and coupled effects of aging and dry-wet cycling were measured by the simple performance tester (SPT) system, and the dynamic modulus principal curves were fitted based on the sigmoidal function. The results show that under the aging effect, the dynamic modulus of asphalt mixture increases with the aging degree; the dynamic modulus of short-term aged, medium-term aged, long-term aged, and ultra-long-term aged asphalt mixtures increased by 9.3%, 26.4%, 44.8%, and 57%, respectively, compared to unaged asphalt mixtures at 20 °C and 10 Hz; the high-temperature stability performance is enhanced, and the low temperature cracking resistance performance is enhanced; under the dry-wet cycle, the aging effect of asphalt water is more obvious in the early stage, and dynamic modulus of resilience of the mixture is slightly increased. In the long-term wet-dry cycle process, water on the asphalt and aggregate erosion increased, the structural bearing capacity attenuation, and the dynamic modulus of rebound greatly reduced at 20 °C and 10 Hz. For example, the dynamic modulus of asphalt mixtures with seven wet and dry cycles increased by 3% compared to asphalt mixtures without wet and dry cycles, and the dynamic modulus of asphalt mixtures with 14 cycles of wet and dry cycles and 21 cycles of wet and dry cycles decreased by 10.8% and 16.5%, respectively, compared to asphalt mixtures without wet and dry cycles. The main curve as a whole shifted downward; the high-temperature performance decreased significantly; in the aging wet-dry cycle coupling, the aging asphalt mixture is more susceptible to water erosion, and the first wet-dry cycle after the mix by the degree of water erosion is relatively small, along with the dynamic modulus of rebound. The dynamic modulus of resilience is relatively larger, and the high-temperature performance is relatively better, while the low-temperature performance is worse.
为研究湿热环境因素对沥青混合料力学性能的影响，本文采用简单性能测试仪（SPT）系统测定了老化、干湿循环以及老化与干湿循环耦合作用下沥青混合料的动态模量，并基于 sigmoidal 函数拟合了动态模量主曲线。结果表明，在老化作用下，沥青混合料的动态模量随老化程度增加；在 20℃、10Hz 时，短期老化、中期老化、长期老化和超长期老化沥青混合料的动态模量分别比未老化沥青混合料提高了 9.3%、26.4%、44.8%和 57%；高温稳定性性能增强，低温抗裂性能增强；在干湿循环作用下，沥青水分的老化作用在初期较为明显，混合料的回弹动态模量略有增加。在长期干湿循环过程中，水分对沥青和集料的侵蚀加剧，结构承载能力衰减，20℃、10Hz 时回弹动态模量大幅降低。例如，经过 7 次干湿循环的沥青混合料的动态模量比未经过干湿循环的沥青混合料提高了 3%，而经过 14 次干湿循环和 21 次干湿循环的沥青混合料的动态模量分别比未经过干湿循环的沥青混合料降低了 10.8%和 16.5%。主曲线整体下移；高温性能显著下降；在老化与干湿循环耦合作用下，老化沥青混合料更易受到水侵蚀，混合料初次经过干湿循环时受水侵蚀程度相对较小，回弹动态模量相对较大，高温性能相对较好，而低温性能较差。
