Table 7 Characteristic points of the skeleton curves.
Specimen | Crack point | Yielding point | Ultimate point | Ductility coefficient | |||
|---|---|---|---|---|---|---|---|
Displacement (mm) | Load (kN) | Displacement (mm) | Load (kN) | Displacement (mm) | Load (kN) | ||
Tube1 | 4.0 | 17.0 | 23.3 | 44.2 | 115.0 | 59.1 | 4.94 |
Tube2 | 6.0 | 33.6 | 16.0 | 51.0 | 114.0 | 67.4 | 7.13 |
Tube3 | 8.0 | 31.8 | 27.5 | 62.5 | 64.0 | 79.8 | 2.33 |
Tube4 | 10.0 | 38.4 | 22.8 | 56.2 | 99.0 | 74.4 | 4.34 |