GPR and LiDAR Synergy: Honeycomb detection in Concrete Structures

Abstract

Honeycombs are formed due to trapped air voids around the coarse aggregates during concreting. These can form inside the concrete structures and on the surface as well. Detecting honeycomb concrete structures is essential to ensure the structural integrity and durability of the structure. However, detecting internal honeycombs are much cumbersome as it is not visible to naked eyes. Ground Penetrating Radar (GPR) is a system that emits and receives Electromagnetic waves which can penetrate through different materials and could detect any disturbances on its travel path. Using the GPR output data, we can identify the defects, honeycombs. Further, Laser imaging Detection and Ranging (LiDAR) emits and receives Laser waves to acquire surface details and reconstruct 2.5D models as Point Clouds. Each of these systems has individual drawbacks. By combining both the systems we can produce data sets that can be used to reconstruct a full 3D understanding of the structure and to conduct further analysis. This paper reviews the pros and cons of GPR and LiDAR and proposes a method on how a full 3D understanding can be obtained using both of these systems and the limitations in the real-world applications of this synergy.