Experimental Evaluation of Bond Properties in Textile-Reinforced Concrete by Digital Image Correlation

The advancement in construction technology leads to the development of sustainable structural systems with a motive of minimal natural resources usage, lightweight, and slender with added economic benefits. To attain this, the studies are evolved to alter partially conventional reinforcement with short fibers. However, the nonuniform distribution of fibers and the difficulty to achieve targeted slender sections resulted in the development of continuous fiber concrete, also termed textile-reinforced concrete (TRC). Due to its non-metallic property, concrete cover can be reduced, which allows for slender and lightweight structural systems. Even though TRC possesses vast possibilities in terms of its usage, the bond–slip relationship is very difficult to identify experimentally, and design standards are still in the research stage. This study aims to determine bond–slip at interface experimentally and explain how the bond length influences the overall performance of the textile-reinforced composite. The bond performance of TRC was assessed on tensile specimens, utilizing double-sided pullout tests with different anchorage lengths. The anchorage length is limited by creating two-sided notches, making sure that only one fiber is tested. The samples are reinforced with one layer of carbon textile coated with epoxy. The bond effect is measured in the form of applied load versus the displacement using the digital image correlation (DIC) technique. Multiple images are collected and analyzed using GOM correlate tool, and a detailed bond behavior is visualized with the increase in the loading. The failure due to rupture and pullout are observed in experiments and pullout load–slip curves are obtained. The results were compared with local bond stress–slip interface models, where shorter bond length experimental results are in good agreement.