平整度水平对沥青路面疲劳破坏的影响

胡朋¹，迟连阳^1*，王琨¹，杜海伦²，管清泳²

1.山东交通学院交通土建工程学院，山东 济南  250357；2.山东舜都路桥工程有限公司，山东 潍坊  262200

摘要：为分析路面平整度引发的动荷载对沥青路面的影响，建立五自由度车辆弹性振动模型，计算车辆在不同行驶速度下的动荷载系数；建立路面结构模型，采用动态弹性模量表征材料的黏弹性特征，以动荷载为输入变量，通过实例分析特定沥青路面结构的动态响应，计算疲劳开裂次数，以静荷载作用下的疲劳寿命为基准计算疲劳寿命比。结果表明：沥青混凝土AC-13的动态弹性模量随大气温度的升高而减小，随加载频率的增大而增大；加载频率对水泥稳定碎石和石灰稳定土的动态弹性模量影响较小，水泥稳定碎石和石灰稳定土的应变越大，动态弹性模量越小；大气温度和路面平整度引发的动荷载对路面疲劳开裂寿命有较大影响，国际平整度指数不大于3.4 m/km时，动荷载作用下的路面疲劳破坏小于静荷载； 国际平整度指数大于3.4 m/km时，动荷载作用下的路面疲劳破坏大于静荷载。

关键词：沥青路面；路面平整度；动荷载；路面响应；疲劳寿命

Influence of surface evenness level on fatigue failure of asphalt pavement

HU Peng¹, CHI Lianyang^1*, WANG Kun¹, DU Hailun², GUAN Qingyong²

1.School of Transportation and Civil Engineering, Shandong Jiaotong University, Jinan 250357, China；

2. Shandong Shundu Road and Bridge Engineering Co., Ltd., Weifang 262200，China

Abstract:In order to analyze the influence of dynamic load caused by surface evenness on asphalt pavement, a five-degree-of-freedom vehicle elastic vibration model is established to calculate the dynamic load coefficient of vehicles at different driving speeds. The pavement structure model is established.The viscoelastic characteristics of the material is characterized with the dynamic elastic modulus.Dynamic load is taken as the input variable. The dynamic response of the specific asphalt pavement structure is analyzed through examples, and the fatigue cracking times are calculated. The fatigue life ratio is calculated based on the fatigue life under static load. The results show that: The dynamic elastic modulus of asphalt concrete AC-13 decreases with the increase of atmospheric temperature and increases with the increase of loading frequency; Loading frequency has little influence on dynamic elastic modulus of cement stabilized macadam and lime stabilized soil is;The greater the strain of cement stabilized macadam and lime stabilized soil is, the smaller the dynamic elastic modulus is. The dynamic load caused by atmospheric temperature and surface evenness has a great influence on the fatigue cracking life of pavement. When the international roughness index is not greater than 3.4 m/km, the fatigue failure of pavement under dynamic load is less than that under static load; When the international roughness index is greater than 3.4 m/km, the fatigue failure of pavement under dynamic load is greater than that under static load.

Keywords:asphalt pavement; surface evenness; dynamic load; pavement response; fatigue life