差异沉降段沥青混凝土路面的疲劳模拟与寿命预估  

Fatigue Simulation and Fatigue Life Prediction of Asphalt Pavement Cracking in Differential Settlement Section

作　　者：刘佳音[1] 陈静云[1] 孙依人 付佳伟[2] 

机构地区：[1]大连理工大学交通运输学院,大连市116023 [2]中交公路规划设计院有限公司,北京市100088

出　　处：《公路》2014年第4期1-5,共5页Highway

基　　金：国家自然科学基金资助项目;项目编号50578031;国家自然科学青年基金资助项目;项目编号51208080

摘　　要：采用两对边简支条件下沥青混凝土板弯曲疲劳试验,模拟差异沉降段沥青混凝土路面的受力状态,研究回填不良对路面结构疲劳寿命的影响。采用往复移动的试验轮模拟移动荷载,使对边简支的板式试件内产生弯拉应力,测定裂缝发展到试件边缘时的疲劳寿命。通过有限元方法,计算常规路段和差异沉降段的弯拉应力。板式试件疲劳试验显示了以横向为主的裂缝分布,这与回填不良区段路面的开裂规律相吻合。结合弯拉应力和板式试件疲劳方程可知,在85%压实度下,沉降区路面疲劳寿命折减为常规路段的13%。文中对差异沉降段开裂现象的研究,有助于对此类病害的预防和处治。The fatigue cracking phenomenon and fatigue life of asphalt pavement in differential settlement section are studied based on fatigue test. The opposite-edge supported slab is adopted to simulate actual pavement mechanical condition. Bi-directional bending stresses are generated in the opposite-edge supported slab through a cyclic moving wheel load. The fatigue life of specimen is determined at the time crack hits the edge. The bending stress in actual pavement structure is calculated by Finite Element Method. The fatigue test shows longitudinal crack consistent with the observed crack pattern in actual differential settlement section. Combining with tensile stress and fatigue equation from slab test, it is concluded that with 85% compactness the fatigue life of pavement reduced to 13% of the conventional sections. This study of cracking generated in differential settlement section provides great significance on the prevention and treatment of fatigue cracking in asphalt pavements.

关 键 词：沥青混合料 差异沉降 疲劳开裂 板式试件 疲劳寿命 

分 类 号：U416.217[交通运输工程—道路与铁道工程]