季冻区OGFC沥青混合料车辙预估模型研究

Research on Rutting Prediction Model of OGFC Asphalt Mixture in Seasonally Frozen Zone

目的研究季冻区OGFC沥青混合料的高温抗车辙能力,建立车辙预估模型,推广OGFC沥青混合料在季冻区的应用。方法采用车辙试验系统进行车辙试验,分析轴载作用次数、试件高度、温度、抗剪强度、冻融循环次数对OGFC沥青混合料车辙深度的影响;基于经验法建立季冻区OGFC沥青混合料车辙预估模型,通过最小二乘法拟合模型参数,对建立的预估模型进行室内试验验证以及有限元对比分析。结果各影响因素与车辙深度呈现幂函数关系,冻融循环作用加速车辙形成,室内试验实测车辙深度与模型预估的车辙深度相对误差为0.11%~9.81%。结论经验法建立的季冻区OGFC沥青混合料车辙预估模型预估精度较高,预估模型误差受试验条件和材料参数影响,其中材料参数影响较明显。

In order to promote the application of OGFC asphalt mixture in seasonal frozen area,the high temperature rutting resistance of OGFC asphalt mixture in seasonal frozen area is studied,and the rutting prediction model is established,then a rutting test system was used to conduct rutting tests,analyzing the effects of axle load cycles,specimen height,temperature,shear strength,and freeze-thaw cycles on the rutting depth of OGFC asphalt mixture.Based on the empirical method,the rutting prediction model of OGFC asphalt mixture in seasonal freezing zone was established.The parameters of the model are fitted by the least square method,and the established prediction model was verified by indoor tests and compared with the finite element analysis.There is a power function relationship between the influencing factors and the rutting depth.The freeze-thaw cycle accelerates the formation of rutting.The relative error between the measured rutting depth and the predicted rutting depth of the model is 0.11%~9.81%.The rutting prediction model of OGFC asphalt mixture in seasonal frozen zone established by the empirical method has high prediction accuracy.The rutting prediction model of OGFC asphalt mixture in seasonal frozen area established by the empirical method has high prediction accuracy.The error of the prediction model is affected by the test conditions and material parameters,among which the material parameters are more obvious.