路面冻胀开裂热-应力耦合分析

Analysis of Thermal-stress Coupling of Pavement Frost Heave Cracking

为了更有效防治季节性冰冻地区道路病害,对路面冻胀开裂力学机理进行了研究。通过对路面冻胀开裂病害现象的调查分析,指出半刚性基层冻胀是道路冻温开裂病害发生的重要因素之一;建立了道路结构热-应力有限元模型,对路面在半刚性基层冻胀作用下的力学响应进行了计算与分析,提出了基于基层冻胀的路面劈裂破坏理论;通过对路面开裂判据应力计算,分析了路面冻胀开裂对冻温材料力学性能变化的敏感性。结果表明,基于半刚性基层冻胀的路面劈裂破坏理论,能够更合理地解释路面冻胀开裂现象;半刚性基层的冻胀性能以及路面材料的强度特性,均对路面冻胀开裂有较大的影响作用。

In order to reduce the destruction of pavement caused by frost heaving in seasonal frost region, the mechanical principles of pavement frost heave cracking was studied. Through investigation and analysis of engineering phenomena of road pavement frost heave cracking, it is indicated that frost heave of semi-rigid base is an important cause of pavement freezing season cracking. The finite element model for thermal-stress coupling of road structure was established to analyze the effect of semi-rigid base frost heave and the mechanical response of pavement, then the pavement splitting failure theory based on base frost heave was put forward. For further information, the pavement cracking criterion stress was calculated, the sensitivity of pavement frost heave cracking to the mechanical property of frozen material was also analyzed. The results show that （ 1 ） the pavement splitting failure theory based on frost heave of semi-rigid base can give a more reasonable explanation for road pavement frost heave cracking; （2） both frost heave performance of semi-rigid base and strength index of pavement material have remarkable influence on pavement frost heave cracking.