An efficient forward model of ground penetrating radar for sensing deteriorated bridge decks

Ground penetrating radar (GPR) is a viable tool for fast nondestructive sensing of concrete structures. The finite difference frequency domain (FDFD) method can be used to simulate subsurface wave scattering. A full 3D FDFD is preferred in general but is computationally burdensome. In this paper, we study deteriorated concrete bridge decks via a comprehensive full 3D analytic method. The Green´s function analysis in combination with the method of moments (MoM) is used to effectively model a layered concrete structure with an embedded grid of rebars. The scattering effect of subsurface defects is computed efficiently via the Born approximation. The analytic method is validated well with the FDFD method.