通过引入稳定的损害极限和记忆效应,对盾道段的疲劳损害演变的创新见解
Yang Zou1, Yichao Ye2, Qianlong Tang1
1School of Civil Engineering, Central South University, Changsha 410075, China.
Materials (Basel, Switzerland)
|February 26, 2025
概括
最初的损伤显著影响屏蔽道段的性能,可能会使损伤率增加十倍. 存在一个关键值,超出这个值后,损坏会迅速加速,导致故障.
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:
- 盾牌道是关键基础设施,需要强大的疲劳设计.
- 了解初始损坏对混凝土段的影响对于结构完整性至关重要.
研究的目的:
- 调查最初受损的盾牌道段的疲劳损伤特征.
- 分析初始损坏和周期性负载对细分业绩演变的影响.
主要方法:
- 对盾牌道的机械边界条件的实验模拟.
- 通过低能耗冲击制造最初受损的混凝土样品.
- 多阶段循环负荷测试,以评估疲劳损伤.
- 分析动态应变,平均应变和应变幅度的时间历史曲线.
- 基于弹性模量降解的损伤演变曲线的推导.
主要成果:
- 最初的损坏和负载水平显著影响了细分业绩的演变.
- 由于最初的损伤,损伤演变速度可以增加十倍或更多.
- 在损伤进化过程中观察到"记忆效应".
- 确定了一个关键值,区分稳定和加速损伤阶段.
结论:
- 超过关键值会导致加速损坏和潜在的故障.
- 对于疲劳设计,引入了"稳定损伤极限"的概念.
- 最初的损伤在混凝土段的非线性拉伸发展中起着至关重要的作用.
- 结果为改善结构混凝土元素的疲劳设计策略提供了见解.
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