摘要 车辙病害是沥青路面主要病害之一，严重影响路面行车安全性和舒适性，尽管基前圈肉终研究学者在如何控制沥青混凝土路露的永久变形方面做了大量的研究工作，提出了一些相应的控制指标，但都没有达到预期的效果，沥青混凝±路面的车辙现象依然十分普遍，尤其是在重载交通和高温地区沥青路面车辙损坏现象更严重。我国由于相关辆轴载限制的法制法规不健全，公路上行驶的重轴载车辆比例逐年提高，超载现象日益严重，某些沥青路砸在开放交通不久就形成过量车辙。而我国瞄前沥青路面设计规范和沥青混合料组成设计方法并不能有效控制重载交通条件下路面车辙的产生，因此从我国道路交通状况的实际出发，如何找到行之有效的控制沥青混凝土路面产生永久变形的方法、提出合理的控制指标是当前沥青路面车辙变形研究一个亟待解决的问题。 论文首先从我匿道路交逶车辆赘载状况调查分析入手，在瓣现有交通资料的分析及现场交通调查的基础上，总结分析了重载交通组成和轴载分布的特点，根据重载交通的基本特征对沥青路面车辙病害展开详细调查研究，分析了重载交通沥青路面车辙病害的横向分布形态特征、产生原因和主要影响因素，明确了本文基于沥青路面车辙病害的重载交通研究重点。 其次，论文选取凡静典型沥青路面结构，考虑沥青路面在重轴载作用下轮胎接地压力分布的非均匀性、面层沥青混合料的粘弹性特性和路面基层面层间的实际接触摩擦状态，采用有限元方法进行力学嚷应非线性计算分析，褥出了影响沥青路面车辙交形的主要力学指标随轮载大小和作用次数的变化规律，进行了沥青两层剪切变形对轮载大小和路面结构参数的敏感性分析。 论文在归纳总结国内外沥青路面车辙预估方法基础上，考虑重载交通条件下沥青路面受力特性，选取SMAl6、AKl6A和ACl6I三种不同类型沥青混合料在不同试验条件下合料进行室内重复加载蠕变试验，对试验结果进行拟合分析得出了沥青面层永久变形的预估模型，建立了考虑沥青面层最大剪应力和沥青混合料孔隙特性的沥青路面车辙预估方法，给出了该车辙预估模型中餐预估参数的确定方法，通过算例验证了本文车辙预估方法的可靠性。 从沥青路面车辙病害角度出发，论文对重载交通沥青路面结构设计方法和设计指标进行了初步研究，给出了基于路面率辙等效原则的轴载换算方法，建议对重载条件下沥青路面结构设计应该在我国现有沥青路面设计方法基础上增加沥青面层最大剪应力和路面设计年限内车辙深度验算指标，以期对重载交通沥青路面车辙产生起到有效控制作用。 关键词：重载，沥青路面，非均布荷载，剪应力，车辙病害，车辙预估，蠕变，重复加载，设计指标 ABSTRACT Rutting is one of the primary damage in the asphalt Mixture pavement,it influences theSafety and comfort of the nmningvehicleseverely．Although a lot of research about controlling the permanent deformation of asphalt pavement have beendone and some rutting dominating indices have been obtained in recent years, rutting phenomenon of asphalt pavement can not be controlled as expected, rutting damage is still serious, especially under heavy load traffic conditions．Because some pertinent legal system and traffic rule of axle load limit are not perfect, the percent of heavy axle vehicle increases gradllally year by year, over loading phenomenon becomes more and more serious, even superfluous rutting of some asphalt pavement appears just a few month after the road is open traffic．The current asphalt pavement designing criterionand the asphalt mixing ratio designing method of our country can not control the rutting development of the asphalt pavement under heavy load．Effectively, so, the valid controlling measure of the permanent deformation of asphalt pavementand the reasonable rutting dominating indices are the key problem expectingt to solve on the research of the asphalt pavement rutting． Firstly, based on the studying of relevant reference data and locale investigation about heavy-duty, the traffic composing and the axial spectrum characteristics of heavy-duty loading are analyzed．According to the characteristics of the heavy duty, the detailed investigation of rutting damage is performed, the distributing characteristics of the rutting transverse profile，the master causes and influencing factors are analyzed． Secondly, the mechanica lresponse of some typical asphalt pavement structures is computed by means of nonlinear finite element method, the non-uniform tire contacting pressure and the visco-elastic characteristics of the asphalt mixture, the contacting and frictional condition between the pavement layersa are taken into consider in the finite element analysis．With the increasing of the axle-1oad and the repeating number, the changing regularity of the primary mechanical index influencing the pavement ruttingis obtained. Three kinds of asphalt mixture(SMA16, AK16A, AC161)are used to perform the cycling loading creep test, the estimating model for the plastic deformation of asphalt mixture is obtained by means of fitting analysis from the experiment data．Taken mechanical characteristics the asphalt pavement under heavy vehicle intoc onsideration, the rutting estimating method including the factors of the maximum shear stress and the asphalt mixture voids is established．In the mean time，thecomputing method of the parameters for the rutting estimating model is given too．The process of the rutting depth computation is illustrated to conform the reliability of the estimating model. From the pointof the rutting damage，the elementary research on the asphalt pavement structure designing method and thedesigning index is executed, the axle conversion method for the heavy loading based on the equivalent principle of ruttingis established also．Finally, the maximum shear index and the rutting depth index of the asphalt layers are suggested affiliating into the current criterion for the asphalt pavement design. Key words: heavy-Duty Loading, asphalt pavement, Non-uniformly Distributed Loading, shear stress, rutting damage, rutting estimation,creep, cycling-loading, design index |
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