Study on seismic performance of steel fiber reinforced concrete shear walls with hybrid steel strands and HRB400 bars in the boundary elements

Abstract

The paper proposed a type of reinforced concrete (RC) shear walls both replacing steel bars in boundary elements with steel strands and adding steel fibers. Four specimens, including one RC specimen, one steel strands RC (SRC) specimen, and two SSFRC specimens referred to SRC specimens using SFRC, were designed and tested to investigate the influences of steel strands in the boundary elements and steel fiber volume ratios (SFVRs) on the seismic performance of proposed shear walls. The results showed adding steel fibers could significantly reduce the damage level of shear walls. Both reinforcing steel strands in the boundary elements and using SFRC could efficiently enhance the bearing capacity and resilient capacity of shear walls, and increased with the increasing SFVRs. Compared with RC shear wall, the peak loads of the SSFRC shear walls with 0%, 0.75% and 1.50% SFVRs increased by 15.8%, 27.7% and 34.5%, and the residual displacement of them decreased by 49.3%, 59.0% and 63.1% at 2.00% loading level, respectively. In addition, reinforcing steel strands in the boundary elements significantly reduced the energy dissipation of shear walls, but using SFRC could enhance the energy dissipation. As the SFVRs increased to 1.50%, the final cumulative energy dissipation of SSFRC shear walls was similar to that of RC shear walls. Finally, the calculation methods for cracking load, steel yielding load and peak load of the SSFRC shear walls were proposed, and the acceptable accuracy was verified by comparing the calculated and experimental results.