TLS Technology in Brick Walls Inspection

Abstract

In the paper authors present the limitations and possibilities associated with terrestrial laser scanning technology in diagnostics of brick walls. The research was conducted in both lab and field conditions. Specially prepared samples were used for lab tests. Field tests were performed on a real building. Measurements were carried out using pulsed TLS scanner Leica ScanStation C10. Defects of flat brick surfaces were located using an algorithm based on Mean Sum Error. In this method a regression is harnessed to find an optimal reference surface. Specifying the reference surface was the basis for detecting cavities. Influence of a scan density, laser beam divergence and spot size on the effectiveness of scanning brick facades was discussed. Generally, the higher scan density, smaller the spot size and smaller laser beam divergence the higher the definition of the survey. The research results show that the surface delamination (cavities, cracks) of bricks facades can be effectively detected by a terrestrial laser scanning system.