“…General GPR applications on roads and streets can be divided roughly into four main categories: (1) surveys carried out in design of a new road, (2) surveys needed for the rehabilitation design of an existing road, (3) quality control or quality assurance surveys on a road project and (4) surveys for pavement management systems and similar purposes (see Saarenketo, 1992;Fernando et al, 1994;Hugenschmidt et al, 1996;Scullion and Saarenketo, 1998;Saarenketo and Scullion, 2000;Saarenketo, 2001;Scullion, 2001;Maser, 2002a,b;Ahmed et al, 2003;Al-Qadi et al, 2003c;Johansson et al, 2005). General GPR applications on roads and streets can be divided roughly into four main categories: (1) surveys carried out in design of a new road, (2) surveys needed for the rehabilitation design of an existing road, (3) quality control or quality assurance surveys on a road project and (4) surveys for pavement management systems and similar purposes (see Saarenketo, 1992;Fernando et al, 1994;Hugenschmidt et al, 1996;Scullion and Saarenketo, 1998;Saarenketo and Scullion, 2000;Saarenketo, 2001;Scullion, 2001;Maser, 2002a,b;Ahmed et al, 2003;Al-Qadi et al, 2003c;Johansson et al, 2005).…”