ABSTRACT
Road tunnels have become key infrastructures as they improve the transportation capability and increase highway efficiency. Consequently, they require accurate routine inspections in order to avoid incidents and extend their life cycle. Both non-destructive, laser scanning and ground penetrating radar technologies are rapidly expanding for exploration in underground environments: LiDAR has been used to model the external geometry; ground penetrating radar is presented for routine sub-surface inspections. In this chapter, their fundamental principles are explained, former applications are introduced and new approaches for underground tunneling prospection and quality detection are discussed through several case studies.
