冻融循环对沥青混合料力学性能的影响  

The effects of the freeze-thaw cycle on the mechanical properties of the asphalt mixture

作　　者：李兆生[1] 谭忆秋[1] 吴思刚[1] 杨福祺 

机构地区：[1]哈尔滨工业大学交通科学与工程学院,黑龙江哈尔滨150090

出　　处：《哈尔滨工程大学学报》2014年第3期378-382,共5页Journal of Harbin Engineering University

基　　金：国家自然科学基金资助项目(50808058)

摘　　要：通过冻融循环作用沥青混合料力学性能的对比分析,研究了冻融对沥青混合料力学性能的影响规律。分析了冻融作用后沥青混合料的高温性能、强度、模量及疲劳性能的变化规律,研究了冻融作用下沥青混合料的损伤特性。研究表明,冻融循环作用后沥青混合料稳定蠕变期的蠕变速率增大,冻融循环作用增大了沥青混合料的高温稳定性对应力水平的敏感性;沥青混合料的抗压强度及回弹模量均随冻融循环次数的增加而降低,损伤变量的变化随冻融次数的增加分为快速损伤期、稳定损伤期及损伤发展期3个阶段;冻融作用后,沥青混合料的抗疲劳性能降低,疲劳寿命对应力水平的变化更为敏感。Through a comparative analysis of the mechanical properties of asphalt mixture affected by freeze -thaw cy-cles, the effects of the freeze-thaw cycles on the mechanical properties of the asphalt mixture were investigated .The change laws of high temperature performance , strength , the modulus and fatigue performance of the asphalt mixture after the freeze-thaw cycles were analyzed , and the characteristics of the damage were also determined .The investi-gation shows that the creep rate of the asphalt mixture increases at a stable creep stage after the freeze-thaw cycles , and the freeze-thaw cycles magnify the effects of the high temperature stability of the asphalt mixture on the sensitiv-ity of the stress level .Meanwhile , with the increase of the number of freeze-thaw cycles , the compressive strength and rebound modulus of the asphalt mixture decrease , and the variation of the damage variable was divided into three stages, i.e., fast damage period, stable damage period and damage development period .The fatigue perform-ance of the asphalt mixture is reduced , and the fatigue life is more sensitive to the variation of stress levels after the asphalt is suffered by the freeze-thaw cycles .

关 键 词：沥青混合料 冻融循环 力学性能 损伤 疲劳寿命 

分 类 号：U416.2[交通运输工程—道路与铁道工程]