冻融循环作用下连续密级配沥青混合料损伤本构关系研究  

Research on damage constitutive relationship of continuous dense gradation asphalt mixture under freeze-thaw cycles

作　　者：李萍[1] 赵军林 念腾飞 王小波 LI Ping;ZHAO Junlin;NIAN Tengfei;WANG Xiaobo(School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学土木工程学院,甘肃兰州730050

出　　处：《武汉大学学报（工学版）》2023年第3期314-321,共8页Engineering Journal of Wuhan University

基　　金：国家自然科学基金项目(编号:51868047,51668041);兰州理工大学红柳优秀青年人才计划项目(编号:04-062005);甘肃省重点研发计划项目(编号:20YF3GA017);甘肃省自然科学基金项目(编号:20JR10RA171)。

摘　　要：为研究季节性冻土区连续密级配沥青混合料的应力-应变关系以及冻融损伤问题,基于应变等价原理和Weibull分布建立了考虑冻融作用沥青混合料的损伤本构关系。采用冻融循环条件下沥青混合料的单轴压缩试验,分析了冻融循环作用对沥青混合料力学特性的影响,并验证了损伤本构关系的合理性。结果表明,随着冻融循环次数的增加,沥青混合料的力学性能逐渐降低,冻融损伤变量逐渐增大;掺入橡胶粉和苯乙烯(styrenic block copolymers,SBS)可有效提高沥青混合的抗冻性能;所建立的本构模型能够较好地反映冻融作用下连续密级配沥青混合料的应力-应变关系;指数函数能够描述冻融损伤变量的变化规律,为分析冻融作用下沥青混合料的损伤破坏提供了新方法。In order to study the stress-strain relationship and freeze-thaw damage of continuous dense-graded asphalt mixtures in seasonally frozen soil regions,a constitutive relationship considering freeze-thaw effects of asphalt mixture damage is established based on the principle of strain equivalence and Weibull distribution.The uniaxial compression test of asphalt mixture under freeze-thaw cycle conditions is used to analyze the influence of freeze-thaw cycles on the mechanical properties of asphalt mixture and verify the rationality of the damage constitutive relationship.The research results show that the mechanical properties of asphalt mixtures gradually decrease with the increase in the number of freeze-thaw cycles,and the freeze-thaw damage variables gradually increase.The addition of rubber powder and styrenic block copolymers(SBS)can effectively improve the freeze resistance of asphalt mixtures.The established constitutive model can better reflect the stress-strain relationship of continuous dense-graded asphalt mixture under freeze-thaw action.The exponential function can describe the change law of freeze-thaw damage variables,and provide a new method for analyzing the damage and destruction of asphalt mixture under freeze-thaw action.

关 键 词：冻融循环 沥青混合料 损伤演化 本构关系 力学特性 

分 类 号：U416[交通运输工程—道路与铁道工程]