(2) Specimen SPE2

Specimen SPE2 was in the elastic stage with no observable behavior when the horizontal load was less than 140 kN. A slight crack appeared on the lower part of the wall when the load was 160 kN. The wall cracks continued to expand when the load was 280 kN. Then, the specimen yielded locally, and the load was applied by controlling the displacement.

In the displacement control stage, several oblique cracks were observed along the 45◦ direction of the wall, with a length of approximately 100 cm when the displacement was 1.5 δ*y* (Figure 5a). The wall cracks continued to expand and extend to the edge of the wall when the displacement was 2.0 <sup>δ</sup>*y*, thereby forming three principal cracks along the diagonal direction. The local concrete expanded and

fell off at the intersection of the principal diagonal cracks when the displacement was 3.5 <sup>δ</sup>*y*, and the width of the cracks reached 4–5 mm (Figure 5b). A large area of concrete on top of the wall fell off and extended along the principal cracks when the displacement was 4.5 <sup>δ</sup>*y*, thereby forming two dropping areas with a length of approximately 50 cm. The local steel bars were exposed. Numerous steel bars were exposed when the displacement was 5.5 <sup>δ</sup>*y*. Then, the local wall showed holes. The flange at the end of the beam bulged upward (Figure 5c) and the column base buckled (Figure 5d). Finally, the horizontal load was reduced by more than 15%, and the specimen lost its carrying capacity.

**Figure 5.** Local failure of SPE2.
