The Study Of Determining Ground Moisture With Ground Penetrating Radar Fractal Box Dimension

Transportation has become one of the pillar industries of our country's social economy,and it is increasingly important to improve the capacity of highway construction.As an important structure of highway,roadbed directly affects the quality,safety,service life and maintenance of the highway.As an important index affecting subgrade quality,moisture content is of great significance.Moisture content is an important parameter to describe soil properties,which is closely related to the subgrade compaction.It is very important to measure moisture to ensure the effective progress of the project quickly and accurately.In this paper,the fractal box dimension is introduced to study the ground penetrating radar wave,and the propagation process of the ground penetrating radar wave in sand is simulated by COMSOL Multiphusics finite element software.The fractal box dimension of simulated wave is calculated and analyzed.The correlation coefficient of sand moisture content and radar wave fractal box dimension is calculated by Origin software,and the function relation between them is fitted.Meanwhile,the sand moisture content is measured by drying method.And compared with the sand moisture content obtained by fitting formula,the thesis mainly includes the following aspects: Firstly,the calculation model of the ground penetrating radarbox dimension is established.Secondly,this paper uses COMSOL Multiphusics finite element simulation software,combines with calculation model of the ground penetrating radar box dimension,verifys that sand moisture is related to radar box dimension,and uses origin software to obtain formula about both.Thirdly,the sand was determined as fine sand by sand grading experiment,and five trials are designed to verify the sand moisture,compared with the moisture content of fitting formula,the maximum error is 4.83%,which proves the feasibility of the formula.This formula is of reference value for the determination of fine sand moisture,and has certain application value to the corresponding construction.