Author : Hussein H. Karim, Hasan H. Joni and Aram A. Dawood

Ground penetrating radar (GPR) has gained increasing popularity in quality control surveys of new and existing road, highways and other structures in the field of pavement engineering due to its greatest advantages as non destructive testing in comparison to the traditional drill core or other methods as well as costs are low and surveys can be performed quickly and data collection can be 2D or 3D displayed. GPR surveys using different types of antennas (250, 500, 800, and 1000 MHz) were carried out along many traverses at different sites. From the intensive implementation of this technique for pavement engineering investigations, data filtering and post processing give results showed pavement layers thickness estimation, damage detection and diagnosis, inspection and monitoring damaged post-tension bridge deck and piers. Several softwares were used for information extraction, processing and 2D or 3D displaying. 3-D imaging radargrams obtained by special softwares reflect better displays over the deteriorated 2-D sections. However, 2-D imaging radargrams gained by 1 GHz offer massive date collection on a bridge deck can be used to distinguish concrete damaged areas or corroded and deflected reinforcement, besides the reinforcement orientations of the doubly reinforced deck were clearly visible. The migration technique was utilized for reinforcement spacing in bridge pier and deck to restore the real location and shape of the reflecting bar.

Keywords: GPR, HMA, Debonding, Pavement thickness, Post-tension bridge, Amplitude reflection coefficient, Migration technique.

Article published in International Journal of Current Engineering and Technology, Vol.6, No.5 (Oct-2016)