Seismic Response Investigation and Nonlinear Numerical Analysis of Cold-Formed Thin-Walled Steel Tube Truss Shear Walls

In order to satisfy the requirements of seismic capacity of cold-formed thin-walled steel structure in low- and multi-rise buildings, an innovative cold-formed thin-walled steel tube truss (CFSTT) shear wall sheathed with both-side oriented strand board (OSB) was proposed in this paper. Five full-scale specimens of CFSTT shear walls which composed of square cold-formed thin-walled steel tubes, tracks, galvanized V-shaped connectors and OSB panels were tested under low-cyclic loading. The seismic performance of CFSTT shear wall was evaluated in terms of hysteretic behavior, envelop curves, ductility and energy dissipation, etc. Then, a practical nonlinear simplified analysis method of CFSTT shear walls under low-cyclic reversed lateral loading was proposed based on the principle of equivalent tie rod model. The double- and four-limb lattice studs were also simplified as single steel tubes. Besides, a pivot modeling approach was suggested to stimulate the sheathing-to-frame connection. Subsequently, the finite element models of CFSTT shear walls were established based on this simplified method and verified by the experimental data. Numerical and experimental results indicated that CFSTT shear walls exhibited excellent seismic performance, and the accuracy of the simplified of lattice stud was verified. Furthermore, the simplified method proposed in this paper will highly facilitate conducting the nonlinear analysis for shear walls.