Shear Performance of RC Beams Strengthened with Steel Strand Wire Mesh–Reinforced Engineered Cementitious Composites under Cyclic Loading

A steel strand wire mesh (SSWM)–reinforced engineered cementitious composite (ECC), referred to as SSWM-ECC, is a promising composite material for structural strengthening owing to the combination of the high strength of SSWM and the high ductility of ECC. This paper presents an application of SSWM-ECC for shear strengthening of reinforced concrete (RC) beams subjected to cyclic loading. First, cyclic loading tests were conducted on two control beams and five strengthened beams, considering various shear span-to-effective depth ratios, reinforcement ratios of the SSWM, and strengthening schemes. The test results showed that brittle failure and degradation of the shear properties of the strengthened beams were effectively mitigated. Compared to the control beams, the ultimate load, cracking load, service load, ductility, and energy absorption of the strengthened beams increased by 18%–40%, 145%–208%, 35%–126%, 20%–65%, and 58%–96%, respectively. The improvement in shear performance increased with increasing reinforcement ratio of the SSWM and shear span-to-effective depth ratio. In addition, the fully wrapped strengthening method effectively confined the concrete, resulting in a more significant increase in the shear performance of the beams compared to the U-wrapped and both-sided methods. Furthermore, a modified truss arch model was developed to predict the shear strength of the strengthened beams. The results predicted by the proposed model exhibited greater accuracy than those generated by various existing models, including those commonly utilized in the field.