Table 4 Optimization results in the local buckling mode using proportions of groups A, B, and C
| Â | Optimum dimensions | Moment capacity using the original design method (kg.cm) | Moment capacity using proposed equations (kg.cm) | Error % | Area of section (mm2) | ||
|---|---|---|---|---|---|---|---|
a mm | b mm | c mm | |||||
Group A | 533 (21 inches) | 253 (9.95 inches) | 44 (1.72 inches) | 1,006,485 (873.59 kip.inch) | 988,869 (858.3 kip.inch) |  + 1.74 | 2948.381 |
Group B | 533 (21 inches) | 218 (8.6 inches) | 44 (1.72 inches) | 989,214 (858.6 kip.inch) | 947,841 (822.69 kip.inch) |  + 4.18 | 2767.736 |
Group C | 533 (21 inches) | 175 (6.88 inches) | 44 (1.72 inches) | 902,229 (783.1 kip.inch) | 892,217 (774.41 kip.inch) |  + 1.1 | 2535.479 |