基于GPR的路基土介电常数模型优化研究

Optimization of subgrade soil dielectric constant model based on GPR

以3种常见的路基填筑材料(粉土、中砂及砾砂)为试验对象,通过探地雷达测试各试样的介电常数,对介电常数的两种体积混合模型(均方根模型和线性模型)进行验证,并利用MATLAB软件对介电常数的实测值与计算值进行非线性回归。结果表明:介电常数实测值与计算值相差较大,但两者之间有较好的相关性,相关系数达0. 95以上,可利用这种相关性可对原模型进行优化,进而利用优化后的模型来反演路基压实度,为评价路基压实质量提供依据。

Three kinds of common roadbed filling materials（silt, medium sand and gravel sand） were used as test objects. The dielectric constant of each sample was tested by ground penetrating radar, and two volume mixing models for dielectric constant （root mean square model and the linear model） were verified. The MATLAB software was used to perform nonlinear regression on the measured and calculated values of the dielectric constant. The results show that the measured values of dielectric constant differ greatly from the calculated values, but there is a good correlation between them, and the correlation coefficient is above 0.95. This correlation can be used to optimize the original models. The optimization models are used to invert the subgrade compactness and provide a basis for evaluating the compaction quality of the subgrade.