摘要(英) |
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. |
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