Mechanical behavior of a steel tube-confined high-strength concrete shear wall under combined tensile and shear loading

The steel tube-reinforced concrete (STRC) shear wall is a type of composite shear wall that consists of a reinforced concrete shear wall embedded into high-strength concrete-filled steel tube (CFST) columns in the boundary element and/or the center of a shear wall. The use of STRC walls has gained popularity in the construction of high-rise buildings because their performance is superior to conventional reinforced concrete (RC) walls. To study the influence of various parameters (i.e., the number of CFSTs embedded in the shear wall, the shear span ratio, the ratio of the vertical reinforcement, the strength of the concrete outside the embedded steel tube, and the initial tensile stress) on the mechanical properties of an STRC composite shear wall under combined tension and shear forces, tensile shear tests were conducted on 9 specimens whose shear span ratios were less than or equal to 1.0. The experimental results demonstrated that the STRC shear wall retained its high shear capacity and its good ductility under a high axial tensile force. Using statistical analyses, a formula to calculate the bearing capacity of an STRC shear wall was proposed. The calculated values are in good agreement with the experimental results.