摘要(英) |
The main focus of this study is to investigate the influence of the diameter of reinforcement bars on fatigue strength and propose an average vertical stress ratio for the local high-stress concentration zone of the reinforcement bar as a predictive model for fatigue strength based on diameter ratio. Currently, the literature related to the impact of diameter on fatigue strength mainly consists of qualitative descriptions. Therefore, this research aims to analyze the quantitative literature and explore the link between the diameter of reinforcement bars and stress intensity factors associated with fatigue phenomena, which serves as the primary motivation for this analysis.
The first part of the study involves referencing relevant literature and discussing the impact and applicability range of parameters on fatigue strength using regression empirical formulas. In the second part, a finite element model of the reinforcement bar is created using Abaqus software, and the effects of changing the diameter on the local high-stress concentration zone are analyzed. In the third part, the BS [1] fatigue strength standard is adopted as a comparative benchmark, and then predictive models for fatigue strength based on diameter ratio are established in four different modes to find the optimal model. Finally, a comparison of the respective empirical formulas, as well as an extended analysis of the effects of changes in the radius of curvature at the root of the surface of the reinforcement bar section and the ratio of radius to height (r/h), are conducted to provide reference for future research on the fatigue strength of reinforcement bars. |
參考文獻 |
[1] 英國混凝土標準 “Steel for the reinforcement of concrete -Weldable reinforcing steel - Bar, coil and decoiled product – Specification,” BS4449:2005
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[8] 范家豪,「螺紋節鋼筋應力集中之數值推衍及現象討論」,碩士論文,中央大學土木工程研究所,中壢 (2021)。 |