Shear Strengthening of Damaged RC Beams with Hybrid Composite Plates: Fid-Bau Portal

Shear Strengthening of Damaged RC Beams with Hybrid Composite Plates

Baghi, Hadi / Barros, Joaquim A. O. / Rezazadeh, Mohammadali / Laranjeira, João

This paper aims to evaluate experimentally the potentialities of hybrid composite plates (HCPs) for the shear strengthening of reinforced concrete (RC) beams previously subjected to intense damage in shear. A HCP is a thin plate of strain-hardening cementitious composite (SHCC) reinforced with carbon fiber–reinforced polymer (CFRP) laminates. For this purpose, an experimental program composed of two series of beams (rectangular and T cross section) was carried out to assess the strengthening efficiency of this technique. In the first step, the control beams, without steel stirrups, were loaded up to their shear failure and fully unloaded. Then these predamaged beams were shear-strengthened by applying HCPs to their lateral faces using a combination of epoxy adhesive and mechanical anchors. The bolts were applied with a certain torque to increase the concrete confinement. The results showed that the increase in load-carrying capacity of the strengthened predamaged beams when HCPs were applied with epoxy adhesive and mechanical anchors was 2 and 2.5 times the load-carrying capacity of the corresponding reference beams (without HCPs) for the rectangular- and T-cross section beam series, respectively. To further explore the potentialities of the HCPs for shear strengthening, experimental tests were conducted using an advanced FEM-based numerical model. After demonstration of the model’s good predictive performance, a parametric study was carried out to highlight both the influence of SHCC as an alternative to mortar and the effect of torque level applied to the mechanical anchors on the load-carrying capacity of beams strengthened with HCPs.