CRC+AC刚柔复合式路面沥青层开裂分析  

Cracking Analysis of Asphalt Layer of CRC+AC Rigid-flexible Composite Pavement

作　　者：邓凤祥 许路凯 周栩佳 DENG Fengxiang;XU Lukai;ZHOU Xujia(Hunan Communications Research Institute Co.Ltd.,Changsha 410015,China;Changsha University of Science&Technology,Changsha 410114,China)

机构地区：[1]湖南省交通科学研究院有限公司,长沙410015 [2]长沙理工大学特殊环境道路工程湖南省重点实验室,长沙410114

出　　处：《武汉理工大学学报（交通科学与工程版）》2023年第4期722-726,共5页Journal of Wuhan University of Technology（Transportation Science & Engineering）

基　　金：国家重点研发计划(2021YFB2601000);湖南省自然科学基金(2022JJ30598);国家自然科学基金(51878076);湖南省交通运输厅科技进步与创新计划项目(202235)。

摘　　要：文中建立了基于温度和三向非均布荷载耦合作用下有限元仿真模型,结合一定温度下落锤式弯沉仪(FWD)实测的复合式路面实体工程路表弯沉测试结果,验证了建模方法的合理性.通过不利荷位与不利时间下连续配筋混凝土刚柔复合式沥青路面在热力耦合作用下的力学响应分析,揭示沥青层在车辆正常行驶状态和紧急制动状态的开裂风险.结果表明:热力耦合有限元模型计算值与FWD实测值最大误差为9.7%,认为该热力耦合方法基本可靠.最不利的工作时间为低温季节的06:00左右,最不利荷位为车轮荷载刚刚通过CRC层微裂缝的荷位.正常行驶状态下,沥青层轮隙处易产生纵向Top-Down裂缝的出现.沥青层底面CRC层微裂缝附近由于应力集中产生较大的拉剪应力,建议采取设置抗裂层等措施,有利于减少损伤开裂而形成的反射裂缝,延长CRC+AC复合式路面使用寿命.紧急制动状态下,沥青层CRC层微裂缝位置更容易产生裂缝,因此在易紧急制动路段应该采取必要的措施.A finite element simulation model based on temperature and three-dimensional non-uniform load coupling was established.The rationality of the modeling method was verified by the deflection test results of the composite pavement at a certain temperature measured by falling weight deflectometer(FWD).Through the mechanical response analysis of continuous reinforced concrete rigid-flexible composite asphalt pavement under the action of thermal coupling under unfavorable load position and unfavorable time,the cracking risk of asphalt layer in normal driving state and emergency braking state was revealed.The results show that the maximum error between the calculated value of thermo-mechanical coupling finite element model and the measured value of FWD is 9.7%,and the thermo-mechanical coupling method is basically reliable.The most unfavorable working time is around 06:00 in low temperature season,and the most unfavorable load position is the load position where the wheel load has just passed through the micro-cracks in CRC layer.Under normal driving conditions,longitudinal Top-Down cracks are easy to appear at the wheel gap of asphalt layer.Due to the stress concentration,there is a large tensile shear stress near the micro-cracks of CRC layer on the bottom of asphalt layer.It is suggested to take measures such as setting anti-crack layer,which is beneficial to reduce the reflection cracks caused by damage cracking and prolong the service life of CRC+AC composite pavement.In the emergency braking state,cracks are more likely to occur in the micro-cracks of CRC layer of asphalt layer,so necessary measures should be taken in the emergency braking road section.

关 键 词：道路工程 连续配筋混凝土板 复合式沥青路面 热力耦合 开裂分析 

分 类 号：U416[交通运输工程—道路与铁道工程]