Abstract:
The bottom shear walls of flexible skyscrapers might be under tension-bending-shear (TBS) combined conditions during strong earthquakes. The Chinese code recommends configuring section steel to improve such seismic performance, but relevant experimental researches are limited. The low-reversed loading tests were performed on six steel plate-reinforced concrete shear walls (SPCW) to investigate the influences of tension ratio, steel ratio, and shear-to-span ratio on the TBS resistant performance. The results indicated that the TBS action led to a dense fracture distribution, prominent steel hardening, and a shear-tension bending coupled failure in SPCW. As the tension ratio increased, the bearing capacity, initial lateral stiffness, and ductility of SPCW decreased by 22%, 41%, and 39%, respectively. Reducing the shear-to-span ratio increased the bearing capacity and lateral stiffness of SPCW by at least 23%, while increasing the steel ratio and reducing the shear-to-span ratio improved the ductility by 10%. The Chinese code had a better prediction on the shear bearing capacity of SPCW under TBS actions than the codes of other countries. However, there was a lack of attention to the high steel ratio’s influence on the dowel force at fracture surfaces, so correction with the initial steel ratio of the concealed column was suggested.