使用改进的响应表面方法对混凝土弧形大的冷解效应进行研究
Qian Cai1, Miaofan Yang2, Jiangui Yang3
1Nanjing Hydraulic Research Institute, Nanjing, 210029, China. wizertize@foxmail.com.
Scientific reports
|November 6, 2023
概括
混凝土面临着由于结解周期等因素导致材料恶化的风险. 这项研究开发了一种可靠性模型,表明随着时间的推移,混凝土的强度下降,大的故障概率显著增加.
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:
- 混凝土弧形大随着时间的推移而退化,由于气候变化,透和冷解周期,造成风险.
- 现有的研究缺乏全面的可靠性评估,以考虑物质恶化效应.
研究的目的:
- 开发一个预测模型,用于混凝土在融条件下的机械性能.
- 为大建立一个随时间变化的结构可靠性分析模型,考虑到材料退化和不确定性.
主要方法:
- 通过回归分析,创建了一个用于结解周期的具体属性预测模型.
- 用有限元等效应力方法与优化响应表面方法相结合,用于可靠性分析.
- 改进的抽样策略和趋同标准被纳入响应表面方法.
主要成果:
- 弧形大的结构故障概率稳步增加,但在融的早期阶段略有增加.
- 由于混凝土的拉伸强度随着长时间的冷解暴露而降低,堤可靠性的显著而突然的下降发生.
- 开发的模型证明了用于评估梁水完整性的实际应用.
结论:
- 材料的恶化,特别是结解效应,会随着时间的推移对门的可靠性产生重大影响.
- 拟议的模型为评估混凝土门大的长期安全提供了一个强大的框架.
- 这项研究为面临物质退化挑战的类似基础设施项目提供了宝贵的技术支持.
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