Investigation of Reinforced Concrete Inclined Shear Plane Strengthened by U-Wrapped TRM jacket with Different Anchorage Details using Modified Push-off Tests

Abstract

This study was conducted to understand the effects of anchored systems for shear strengthening of an inclined shear plane in reinforced concrete, using an externally U-wrapped textile-reinforced mortar (TRM) jacket. The main test parameters were the textile reinforcement ratios adopted in the TRM composite and the different anchorage details utilized at both ends of the U-wrapped TRM jacket. Two textile reinforcement ratios of 0.152% and 0.304% were adopted for the TRM jacket, corresponding to the use of two and four textile layers, respectively. The investigated anchorage details included (a) fiber-reinforced polymer (FRP) anchors; (b) mechanical anchors; (c) textile-anchored by re-bar inserted in a groove; and (d) textile-anchored by re-bar inserted in a groove, combined with FRP anchors. Modified push-off tests were conducted to partially simulate the development of the 45 degrees diagonal failure plane in reinforced concrete (RC) beams subjected to a combination of shear and tension. The test results indicated the effectiveness of the proposed anchorage details in enhancing the contribution of the TRM jacket to the shear resistance capacity of the specimens, before and after the formation of the critical shear crack. Additionally, the strain of the internal shear reinforcement after attaining peak load considerably decreased, and the effective strain developed in the TRM composite was also ameliorated using the anchorage details.