基于Maxwell方程的沥青混合料介电模型研究

Study on Dielectric Model of Asphalt Concrete Based on Maxwell Equation

为提高沥青路面无损检测精度,明确沥青混合料的介电特性,基于Maxwell方程建立了沥青混合料介电模型,测量多个频率下沥青混合料的相对介电常数,验证了该模型的适用性.并将该模型与Brown模型、CRIM模型和Rayleigh模型的精度进行对比验证其优越性.结果表明:频率是影响沥青混合料相对介电常数的主要因素,当频率增大至1 MHz后沥青混合料的相对介电常数保持稳定.基于Maxwell方程的介电模型与其它三种模型相比拟合精度较高,相对误差仅为0.5%.

In order to improve the accuracy of nondestructive testing of asphalt pavement and clarify the dielectric characteristics of asphalt mixture,the dielectric model of asphalt mixture was established based on Maxwell equation,and the relative dielectric constant of asphalt mixture at multiple frequencies was measured,which verified the applicability of the model.The accuracy of this model was compared with that of Brown model,CRIM model and Rayleigh model to verify its superiority.The results show that frequency is the main factor affecting the relative dielectric constant of asphalt mixture,and the relative dielectric constant of asphalt mixture remains stable when the frequency increases to 1MHz.Compared with other three models,the dielectric model based on Maxwell equation has higher fitting accuracy,and the relative error is only 0.5%.