Study on seismic performance test and calculation method of recycled steel fiber reinforced concrete shear wall

Summary Recycled steel wire is taken from used tires, and by procedures like mechanical cutting and friction treatment, it can be converted into industrial recycled steel fiber that meets precise criteria. Such green fiber may effectively limit the growth of fractures in concrete and diffuse the fracture energy of concrete when incorporated into concrete. An investigation of the effects of materials and horizontal reinforcement spacing on the seismic performance of shear wall specimens is presented in this research. The test and numerical simulation findings indicate that the RSFRC (recycled steel fiber reinforced concrete) shear wall's fracture is substantially narrower than that of a conventional shear wall and that the shear carrying capacity and deformation ductility of the shear wall have been greatly enhanced. The energy dissipation capacity of the RSFRC shear wall specimen with varying horizontal reinforcement spacing is significantly enhanced when compared to the conventional shear wall, and the ultimate displacements are reduced. RSFRC shear wall specimen has higher stiffness in the early stage, and the overall stiffness decreases slowly. With the decrease of fiber volume fraction of RSFRC shear wall in a certain range, the shear bearing capacity and stiffness of the model will decrease slightly, but the ductility will increase significantly. Compared with the RSFRC shear wall with fiber aspect ratio of 40 and 25, the bearing capacity and ductility of the two are close, but the RSFRC shear wall with low aspect ratio is slightly insufficient. When the axial compression ratio is in the range of 0.2–0.4, the horizontal shear capacity of RSFRC shear wall increases with the increase of vertical load, but the maximum horizontal displacement becomes smaller, and the model is damaged by compression. Using theoretical calculation, this work also creates the simplified calculation method and restoring force model for the bearing capacity of the diagonal section of RSFRC shear wall. The observed findings correspond well with the test hysteresis curve and may serve as a benchmark for future study. This study provides a new research direction for the seismic performance of RSFRC structures, as well as a solid theoretical foundation and promotion for future research.