摘要
基于断裂力学基本理论,在有限元方法中利用动态模量主曲线和时温转化因子确定行车速度下的沥青混合料力学性质,采用移动荷载模式,考虑行车速度、荷载及温度对含多裂纹的沥青路面结构进行动力特性分析。研究表明:移动荷载作用下的面层与基层两类裂缝尖端应力因子K1、K2值呈现正负交替的规律;较低的车速和荷载的增加都会加速裂缝的扩展;低温和高温工况下对路面结构都是不利的。面层低温和高温都是以张开型裂缝K1为主导因素,基层低温时以张开型裂缝K1为主导因素,而基层高温时以剪切型裂缝K2为主导因素。
Based on fracture mechanics,the dynamic response of the asphalt pavement with multiple cracks under moving loads was studied by a numerical simulation with the finite element method considering the effects of vehicle speed,loads and temperature. Dynamic modulus curves and time-temperature factors were incorporated into a finite element model to characterize the mechanical properties of asphalt mixtures. The results show that,under the vertical loads,two kinds of crack tip stress factors（ surface course K1,K2 and subbase course K1,K2） are alternated between plus and minus;that the expansion of cracks is accelerated by lower speed and increasing load; that the pavement under low temperature and high temperature are unfavorable; that the dominated factor for the surface crack is the open-type crack（ K1） under low or high temperatures; that the dominated factor for subbase crack under low temperature is the open-type crack（ K1）,while the dominated factor is theshear-type crack（ K2） under high temperature.
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2016年第1期246-252,共7页
Journal of Guangxi University（Natural Science Edition）
基金
西部交通建设科技项目(20033187950
20033187951)
关键词
动态模量
多裂纹
应力强度因子
有限元
dynamic modulus
multi-crack
stress intensity factor
finite element
