|
Title |
Detection and Localization of GFRP Rebars using GPR
|
|
Authors |
박예진(Yaejin Park) ; 임형진(Hyung Jin Lim) |
|
DOI |
https://doi.org/10.11112/jksmi.2025.29.6.134 |
|
Keywords |
지표투과레이더(GPR); B-Scan 이미지; 유리섬유 보강 폴리머(GFRP) 보강근; 공간평균화; 쌍곡선 회귀분석 Ground penetrating radar; B- Scan radargram; GFRP rebar; Spatial averaging; Hyperbola fitting |
|
Abstract |
This study presents the development of a non-destructive Glass Fiber Reinforced Polymer (GFRP) rebar identification technique based on Ground Penetrating Radar (GPR) B-Scan images (radargrams). Conventional steel rebars are vulnerable to corrosion and require costly repairs and maintenance, while GFRP rebars are gaining interest due to their lightweight, non-corrosive, and high tensile strength characteristics. GPR is a non-destructive inspection technique for concrete structures using electromagnetic waves. The existence, location, and diameter of steel rebars can be identified using the electromagnetic waves reflected from them, owing to significant dielectric constant differences with concrete. However, for GFRP rebars, it becomes challenging because the dielectric constant difference between GFRP rebars and concrete is much less than that of steel rebars. Thus, in this study, the existence and location of GFRP rebars are estimated. First, electromagnetic waves reflected from GFRP rebars were enhanced by averaging multiple spatially obtained GPR radargram images to detect GFRP rebars. Then, the location of GFRP rebars was estimated using conventional hyperbola fitting of the reflected electromagnetic waves. The performance of the developed technique was experimentally evaluated using concrete specimens with actual GFPR rebars. The results indicate that GFRP rebars are more clearly identified with this technique, enabling approximate depth estimation.
|