摘要
长期冻融循环损伤作用严重影响高黏高弹沥青混凝土服役安全性与耐久性,依据动力学性能研究其冻融损伤特性、损伤机理及发展规律具有重要现实意义。为此,采用宏细观方法从动力学性能衰减角度研究高黏高弹沥青混凝土的冻融循环损伤问题,通过室内冻融循环试验、动态力学行为分析、沥青流变和黏附性测试及内部细观结构观察明确了其性能衰减规律和冻融损伤机制,优化了性能评价指标和损伤演变模型。研究结果表明:2S2P1D模型的拟合优度在0.98以上,能够较好地反映冻融循环损伤对动态力学性能的影响规律。沥青硬化效应和沥青-集料交互作用劣化的相互竞争机制使得高黏高弹沥青混凝土冻融损伤表现复杂,但冻融损伤后能够在常见缩减频率[10^(-3) Hz,10^(3) Hz]中频(中温)区交通荷载和气候环境下保持较好的动态力学性能。高黏高弹沥青混凝土动态力学性能在高频(低温)和低频(高温)区表现出“保持-加速-平衡”的冻融损伤趋势,高频(低温)、低频(高温)极限模量比能够反映内部结构冻融损伤特征,据此建立的损伤演变模型能够较准确地反映内部材料结构劣化规律(判定系数R2>0.95)。研究结果可为高黏高弹沥青混凝土抗冻融性能优化设计与服役耐久性验证提供参考。
Long-term freeze-thaw cycling damage seriously affects the service safety and durability of high-viscosity high-elasticity asphalt concrete,and it is of great practical significance to study its freeze-thaw damage characteristics and explore the damage mechanism and development law according to its dynamic properties.In this study,the dynamic performance and damage evolution behavior of high-viscosity high-elastic asphalt concrete under repeated freeze-thaw cycles were studied from the macroscopic and microscopic points of view,and the performance decay pattern and freeze-thaw damage mechanism were elucidated by laboratory freeze-thaw cycling,dynamic viscoelastic behavior analysis,evaluation of the rheological and bonding performance of the asphalt,and internal structure observation.The performance index and damage development model were optimized on this basis.The results show that the 2S2P1D(2-Springs,2-Parabolic,and 1-Dashpot)model has a goodness-of-fit of over 0.98 and is able to emulate the effects of freeze-thaw cyclic damage on the dynamic performance.The competing mechanisms of the asphalt hardening effect and asphalt-aggregate interaction deterioration cause freeze-thaw damage in high-viscosity and high-elastic asphalt concrete complexes;however,these complexes are able to maintain their dynamic mechanical properties after freeze-thaw damage under common traffic loads and climatic conditions in the mid-frequency(mid-temperature)region.The dynamic properties of high-viscosity,high-elasticity asphalt concrete exhibit a holding-acceleration-equilibrium freeze-thaw damage trend in the high-frequency(low-temperature)and low-frequency(high-temperature)regions.The developed damage evolution model accurately reflected the deterioration of the interior material and structure(R2>0.95).This study serves as a reference for the design and durability verification of high-viscosity and high-elasticity asphalt concrete.
作者
肖鑫
王嘉宇
李进
肖飞鹏
XIAO Xin;WANG Jia-yu;LI Jin;XIAO Fei-peng(College of Transportation Engineering,Tongji University,Shanghai 201804,China;School of Architecture and Civil Engineering,Chengdu University,Chengdu 610106,Sichuan,China)
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2023年第12期64-76,共13页
China Journal of Highway and Transport
关键词
路面工程
沥青混凝土
高黏高弹
冻融循环
动态模量
2S2P1D模型
pavement engineering
asphalt concrete
high-viscosity high-elasticity
freeze-thaw cycle
dynamic modulus
2S2P1D model
