常规平面混凝土和钢筋混凝土在弹性负荷下拉伸疲劳性能
Huating Chen1, Zhenyu Sun1, Xianwei Zhang2
1Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, China.
Materials (Basel, Switzerland)
|October 14, 2023
概括
这项研究研究了桥梁中的普通混凝土的屈曲疲劳行为. 使用S-N方程和韦布尔分布分析了疲劳寿命,揭示了压力比率作为关键因素.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
背景情况:
- 桥梁组件因车辆负载和温度变化而面临循环应力,风险是混凝土疲劳失效.
- 现有的混凝土疲劳数据主要涵盖低强度路面和高强度结构类型,对普通桥梁混凝土有差距.
- 了解C50混凝土的疲劳性能对于桥梁的耐用性和可持续性至关重要.
研究的目的:
- 研究用于桥梁工程的普通混凝土 (C50) 的屈曲疲劳行为.
- 为了确定在疲劳负荷下混凝土的循环变形演变.
- 建立实证疲劳S-N方程并分析疲劳寿命分布.
主要方法:
- 在97个C50混凝土样本上进行了四点曲疲劳测试,在恒定幅度的正弦负荷下.
- 研究了平面和钢筋混凝土样品的屈曲疲劳性能.
- 使用统计方法分析测试结果,以导出S-N方程和韦布尔分布参数.
主要成果:
- 获得了混凝土的实证疲劳S-N方程,故障概率从0.1到0.5.5不等.
- 疲劳寿命遵循一个双参数的韦布尔分布.
- 确定最大应力水平 (Smax) 和应力比率 (R) 作为影响疲劳寿命 (N) 的关键因素.
- 对数方程预测Smax<0.70.0的疲劳寿命比半对数方程更长.
- 钢筋稍微增强了疲劳裂纹启动寿命.
结论:
- 这项研究为桥梁结构中普通混凝土的屈曲疲劳特性提供了关键的见解.
- 开发了疲劳模型,并确定了更好的结构评估的关键影响因素.
- 调查结果支持改善混凝土和复合材料桥梁甲板的耐用性和可持续性评估.
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