Application of GPR technique in evaluation of internal defects in hardwood species

Abstract

Non-destructive testing of materials properties is continuously developing. Ground penetrating radar (GPR) as a non-destructive method is based on the transmission of electromagnetic energy and recently has been applied in field of wood and wood products. In this study, GPR technique was used to evaluate the internal defects in three species hardwood with three moisture content levels. In order to remove determinant extrinsic and uncertain factors, several artificially defects were created within the wood samples. Data collection was done by MALA CX GPR in center frequency of 2300 MHz and processed with Reflexw software. This study showed that dielectric properties on wet-woods are more than that in dry-woods and internal defects woods in wet wood can be detected better than dry woods. However, the holes with diameters of 4 mm and less were not detectable. In general, GPR, as a safe and portable method, is capable for detecting internal defects and voids in hardwood.

Keywords

• Non-destructive testing
• Ground penetrating radar
• internal defects woods
• dielectric properties