Reduction in Stress Intensity Factor of a Compact Tension Specimen by Bonding Symmetrical GFRP Patches

Abstract

Reduction in stress intensity factor (SIF) of an acrylic compact tension (CT) specimen is studied by symmetrical bonding of glass fiber reinforced plastic (GFRP) patches on both sides of the specimen. The CT specimen was designed and developed to satisfy all dimensional constraints for plane strain condition. A suitable load fixture using dead weight for higher accuracy was designed for the purpose. The numerical and experimental analysis of CT specimen with varying geometry of the GFRP patches was carried out to analyze their effect on SIF of the specimen. The strain near the crack tip was measured by bonding a small strain gauge to estimate the equivalent SIF of the CT specimen. The test data was compared with the results of numerical analysis carried out using ANSYS software. The variation in strain value determined through theoretical analysis, numerical evaluation and experimental measurement is within 7 %. The equivalent SIF was found to be drastically reduced after bonding the CT specimen with GFRP patches.