基于动态模量的沥青路面开裂分析  

Cracking Analysis of Asphalt Pavement Based on Dynamic Modulus

作　　者：赵延庆[1] 王国忠[1] 王志超[1] 谭忆秋[2] 

机构地区：[1]大连理工大学交通运输学院,辽宁大连116024 [2]哈尔滨工业大学交通科学与工程学院,黑龙江哈尔滨150001

出　　处：《湖南大学学报（自然科学版）》2010年第7期7-11,共5页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(50778057);交通部西部交通科技建设项目(200831800099)

摘　　要：在有限元方法中利用动态模量主曲线和时间-温度位移因子来考虑荷载作用频率和温度对沥青混合料力学性质的影响,采用移动荷载模式,利用断裂力学的方法分析了典型柔性基层沥青路面的开裂机理.研究表明:轮载经过裂缝1次,根据不同工况,可能在裂尖引起1个,2个或3个张开型应力强度因子(KⅠ)峰值.而剪切型应力强度因子(KⅡ)总有2个峰值,且大小相等,方向相反.分析了温度、行车速度及裂缝长度对裂尖应力强度因子及其作用频率的影响.当裂缝较短且温度较低时,裂缝扩展主要由KⅠ引起.随着裂缝长度的增加和温度的升高,KⅡ逐渐成为裂缝扩展的主要因素.In this study,the dynamic modulus master curves and time-temperature shift factors of asphalt mixtures were incorporated in finite element method to take into account the effects of the load frequency and temperature on the mechanical properties of asphalt mixtures.Bottom-up fatigue cracking of a typical asphalt pavement structure with flexible bases under moving load was analyzed with fracture mechanics.The results showed that one,two or three peaks of tensile type stress intensity factor（KⅠ） at the crack tip could be induced during one passage of wheel load over the crack under various conditions,while two peaks of shear type stress intensity factor（KⅡ） always occurred,which were equal in magnitude but had opposite directions.The effects of temperature,vehicle speed and crack length on stress intensity factor and its frequency were analyzed.It was found that crack propagation was mainly controlled by KⅠ for pavements with short crack length and at low temperature,and KⅡ gradually became the main driving force for crack propagation as temperature and crack length increased.

关 键 词：应力强度因子 温度 行车速度 裂缝长度 移动荷载 动态模量主曲线 

分 类 号：U416.217[交通运输工程—道路与铁道工程]