Ground-penetrating radar (GPR) for non-destructive characterization of reinforced concrete structures

Abstract

Characterizing reinforced concrete structures is an overall evaluation process, including inspection, investigation, and testing of the concrete structures. To investigate existing concrete structures in service is preferred to use non-destructive techniques. For non-destructive investigation of reinforced concrete structures, Ground Penetrating radar (GPR) is a preferred instrument and is worldwide accepted for its ability to detect defects and provision of reliable images of the substructure of concrete structures. Ground penetrating radar (GPR) emits electromagnetic energy waves into the surface of concrete due to encounters with materials having different dielectric constants; waves deflect back and make the display of substructure on radargram.

This thesis work is aimed to find the location of different types of construction defects, foreign objects, and reinforcement details in concrete structures. For this purpose, PS 1000 X-SCAN CONCRETE SCANNER is used to obtain image scans from the thick concrete testing wall, retaining wall and precast RC slabs. GPR scans are analyzed using Profis Detection Software by HILTI to get the required results.

Detection and location of construction defects, rebar mapping, concrete cover depth and location of other anomalies and metal objects in the sub-structure of concrete are beneficial for the maintenance and repair of concrete structures. The service life of concrete structures can be predicted from GPR scanning results using the evaluation of defects leading to failure of the concrete structures.