沥青混凝土单刀铣削阻力计算模型与试验修正

Calculation Model and Test Correction of Single Tool's Milling Resistance Force of Asphalt Concrete

为计算沥青混凝土单刀铣削阻力,在分析其破坏过程和单刀铣削厚度变化特征基础上,将单刀变厚度旋转铣削瞬间过程视为等厚度平移铣削,以刀具铣削合速度为平移切削速度,在Merchant岩石切削模型的基础上,结合沥青混凝土常温剪切破坏特性建立单刀铣削阻力计算模型,分析铣削阻力计算值峰值与实测值峰值间的误差及其来源,并以铣削速比和铣削线速度为自变量对单刀铣削阻力计算公式加以修正。结果表明:在给定相对误差上下限为±15%时,修正后铣削阻力理论计算值的置信度为0.91;单一铣削循环中铣削阻力计算值与实测值随转角变化过程一致,线性相关系数为0.95;计算模型可为单刀铣削阻力的计算及预测提供参考。

In order to calculate single tool＇s milling resistance force of asphalt concrete,the milling failure process and changing process of single tool＇s milling thickness were analyzed.The instantaneous process of single tool＇s varied-thickness rotating-milling was regarded as equal thickness linear cutting process,and resultant milling speed was linear cutting speed.Based on the Merchant＇s cutting model of rock,combining the shear failure characteristic of asphalt concrete at normal temperature,the calculation model of single tool＇s milling resistance force was established.The error between calculated peak-value and measured peak-value of single tool＇s milling resistance force and its source were analyzed.The calculation formula of single tool＇s milling resistance force was corrected taking milling linear speed and milling speed ratio as independent variables.The results show that confidence coefficient of milling resistance calculation value is 0.91 when the upper and lower limit of error is ±15% after correction of the formula.The changes of calculated value and measured value of single tool＇s milling resistance force are consistent with rotation angle in single milling loop,and the linear correlation coefficient is 0.95.The calculation model provides a reference for the calculation and prediction of single tool＇s milling resistance force.