本研究主要為探討三維竹節鋼筋受軸拉力及溫差載重下的應力集中係數與二維軸對稱鋼筋應力集中係數的關聯性，以二維軸對稱模型為基礎以數值經驗公式去推算三維竹節鋼筋應力集中係數。利用三維竹節鋼筋模型建置過程較為繁瑣且分析時間相當耗時，且三維模型也較二維模型難得到精確解，其數值易受到網格大小和網格品質的影響，因此將討論兩者的關聯性，提出三維模型的轉換經驗公式，使得將二維軸對稱模型分析數值代入轉換式即可得出三維竹節鋼筋之應力集中係數，並針對此經驗式不適用的夾角角度範圍提出修正因子，使得修正後的經驗解其數值的準確性能夠提高。 為了能夠提高鋼筋的疲勞強度，鋼筋可以透過適當的熱處理，但鋼筋在高溫條件下，鋼筋若受到膨脹和收縮若受到約束時，會因此在鋼筋表面產生熱應力從而使鋼筋受到疲勞損傷，就是為了避免熱疲勞的發生，如何能夠快速得知鋼筋高應力集中發生的地方是個值得探討的議題。 ;The purpose of this study is to investigate the relationship between the stress concentration factor of the three-dimensional (3D) deformed steel bar caused by the axial tension and temperature difference and the one of the two-dimensional (2D) axisymmetric reinforced steel. The stress concentration factor of the 3D deformed steel bar is calculated according to the numerical empirical formula based on the 2D axisymmetric model. The process of building a 3D deformed steel bar model is time-consuming. In addition, the 3D model is more difficult to obtain the numerical solution than the 2D one, and its numerical value is easily affected by the mesh size and quality; therefore, this study proposes a transformation empirical formula of a 3D model, so the stress concentration factor of the 3D deformed steel bar can be obtained by applying the results of the 2D axisymmetric model to the transformation formula. Moreover, the correction factor obtained by the inapplicable range of the included angle using this empirical formula can improve the numerical accuracy of the corrected analytical solution. Undergoing proper heat treatment for the reinforced steel can increase its fatigue strength. However, high temperature causes thermal stress on the surface of the reinforced steel, and therefore causes fatigue damage. This study aims to avoid the occurrence of thermal fatigue and quickly obtain where the stress concentration of the reinforced steel occurs.
