Ground Penetrating Radar (GPR) has been widely applied in civil engineering and environmental detection as a high resolution and efficient nondestructive testing (NDT) method. For example, it is used to detect the rebar concrete structures. In this paper, the FDTD method was used to simulate the GPR detection of the defects in the reinforced concrete and to migrate with the frequency wavenumber (F-K) migration method. This study shows that the technique can be used to reduce the multiple and diffraction of rebar. With the F-K migration method, the diffraction energy is efficiently focused on rebar and defects, which can not only separate the signals of rebar from those of defects but also improve range resolution. As a result, the distribution and shape of defects can be easily interpreted.
［1］ 周辉,邱东玲.地质雷达数据处理现状和展望［J］.地学前缘,2001,8(2).
［2］ Di Qingyun,Wang Miaoyue.Migration of ground-penetrating radar data with a finite-element method that considers attenuation and dispersion［J］.Geophysics,2004,69(2):472.
［3］ Yee K S.Numerical Solution of Initial boundary value problems Involving Maxwell's Equations in Isotropic Media［J］.IEEE Trans,1966,AP-14(3): 302.
［4］ 王秉中.计算电磁学［M］.北京:科学出版社.2002,120.
［5］ Berenger J P.A perfectly matched layer for the absorption of electro-magnetic waves［J］.Computational Physics.1994,114(2): 185.
［6］ Tillard S,Dubois J C.Analysis of GPR data: wave propagation velocity determination［J］.Applied Geophysics,1995,33:77.
［7］ Jaya M S,Botelho M A,Hubral P.Remigration of ground-penetration radar data［J］.Applied Geophysics,1999,41:19.
［8］ 贺振华.反射地震资料偏移处理与反演方法［M］.重庆:重庆大学出版社.1989.
［9］ Vincenzo Barrile,Raffaele Pucinotti.Application of radar technology to reinforced concrete structures:a case study［J］.NDT&E International,2005,38:596.
