Load Process and Failure Characteristics of Specimens
Specimens were loaded to yield period by controlling 5~7 loading steps. After being yield, specimens were loaded to failure by controlling displacement steps. Each loading stage stayed for about
1. Back-to-back stud; 2. C-shaped stud; 3. Track; 4. Strap;
5. Self-drilling fastener; 6. Gypsum sheathing; 7. OSB sheathing
Fig. 1. Configuration of DSGO wall.
Fig. 3. Failure modes of specimens.
Fig. 4. Load-displacement curves for specimens.
3 minutes. The shear resistance and stiffness of SSG Specimen were lower. As a result, relative rotation was taken place between the two panels of gypsum sheathings, and their vertical connecting seam offset. The gypsum sheathing was tore at the corner of wall perimeter (shown in Figure 3a). The shear resistance strength and ductility of SSO wall were better than that of SSG wall, but the horizontal connecting seam in SSO wall influenced its bearing capacity and stiffness. With the load increasing, the steel strap buckled apparently (shown in Figure 3b), and the slip of the four panels of OSB sheathing was relatively great (shown in Figure 3c), which made the shear stiffness of wall reduced. The integrity, strength and stiffness of DSGO wall excelled that of SSG wall and SSO wall. The failure modes of three kinds of wall were similar. In general, when the failure of all wall specimens was occurred under shear load, most of the screw connecting sheathing and steel members around the wall were failed, and the stud on the end of wall usually locally buckled (shown in Figure 3d). But the gypsum sheathing or OSB sheathing did not drop off integrally due to the less damage of the screw connections in the middle field of wall, so we could conclude that the screws at the perimeter bore higher shear load than those in the middle field.