Evaluation of strain-hardening cementitious composites for RC seismic strengthening

A numerical approach for evaluating the behaviour of strain-hardening cementitious composites (SHCCs) for reinforced-concrete (RC) seismic strengthening is presented. The method takes account of the seismic tensile strain capacity of SHCCs for RC strengthening, which is affected by the presence of cracks within the RC and varying layer thickness of the SHCC, the shear transfer behaviour of SHCC layers on the crack surface, which is contributed to by both the contact effect and the fibre bridging effect on the crack surface, and the seismic compressive constitutive law of SHCCs. In the numerical approach, a zero-span tensile model is adopted for reflecting the tensile strain capacity of SHCCs for RC strengthening, and a shear stress transfer model is applied for reflecting the respective contributions of both contact stress and fibre bridging stress for shear stress transfer behaviour of the SHCC on the crack surface. The effectiveness of the numerical approach is confirmed through the comparison between the experimental investigation and numerical analysis, in which the numerical result is coincided with the experimental one.