本文使用適當的應力-應變關係、模型、網格元素、邊界條件及負載條件，有限元素ANSYS Workbench 17.0可用來模擬分析有相同截面不同方向多餘圓孔的圓孔管在循環彎曲負載下的力學行為。本研究所分析的圓孔管材料為6061-T6鋁合金，其中多餘圓孔與圓孔管的圓孔直徑皆為6 mm，而五種不同角度的多餘圓孔方向分別為:45°、67.5°、90°、135°及180°。至於所探討的力學行為包含有：彎矩-曲率與橢圓化-曲率的關係。
一旦確認ANSYS模擬能準確的描述實驗結果，則每一個循環彎曲負載事件中的最大應力及最小應力即可準確的求得。因為實驗試件的毀損型態是疲勞破壞，因此本文使用一個簡單的疲勞模式來估算疲勞壽命。此外，由於最大應力及最小應力數值上的並無太大的差異，所以平均應力影響不列入考慮。根據分析結果顯示，所提出的疲勞模式能適當的預測有相同截面不同方向多餘圓孔的6061-T6圓孔管在循環彎曲負載下的疲勞壽命。

In this study, the finite element software ANSYS Workbench 17.0 is used to analyze the mechanical response of round-hole tubes with a redundant hole on the same cross-section and different directions under the symmetrical curvature- controlled cyclic bending. The material of the tubes is 6061-T6 aluminum alloy and the hole diameters are 6 mm. The mechanical response includes the moment-curvature and ovalization-curvature relationships. The controlled curvature is from +0.4 m-1 to -0.4 m-1. According to the analysis result, the moment-curvature curves show a stable loop for tubes with or without a redundant hole. However, the ovalization-curvature curves show that the values of ovalization from big to small correspond to the redundant hole directions of 45°, 67.5°,90°, 135° and 180°. By comparing the analysis result for redundant holes at different directions, the moment-curvature curves reveal almost no influence by the variation of redundant hole direction. However, the ovalization- curvature curves show a strong influence by different directions of the redundant hole. Finally, by comparison of the ANSYS analysis and the experimental finding, it can be found that the ANSYS analysis can properly simulate the experimental data.

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