在模拟交通负荷下,钢桥甲板接接接头的疲劳裂的随机传播
Naiwei Lu1,2, Jing Liu1, Honghao Wang1
1School of Civil Engineering, Changsha University of Science and Technology, Changsha 410114, China.
Sensors (Basel, Switzerland)
|June 10, 2023
概括
这项研究提出了一个计算框架,用于预测随机卡车载荷下的正轨钢桥甲板的疲劳裂增长. 了解在随机流量下裂传播是评估桥梁安全和延长结构寿命的关键.
科学领域:
- 结构工程 结构工程
- 材料科学 材料科学 材料科学
- 计算力学 计算力学 计算力学
背景情况:
- 在正体钢桥甲板 (OSD) 中,疲劳裂是一个重大挑战,主要是由于增加的交通负载和卡车超载造成的.
- 随机交通负载使疲劳裂传播的预测和OSD的整体疲劳寿命评估复杂化.
研究的目的:
- 开发一个计算框架来模拟在随机交通负载下的OSD中疲劳裂纹传播.
- 分析交通负载参数对裂行为和压力强度因素的影响.
主要方法:
- 利用特定站点的移动权衡数据建立随机交通负载模型.
- 采用有限元素方法来模拟疲劳应力光谱和裂传播路径.
- 研究了横轮负载位置对应力强度因素的影响.
主要成果:
- 在临界负荷下,最大应力强度系数 (KI) 为568.18 (MPa·mm1/2),当负荷横移450毫米时下降了66.4%.
- 裂纹尖的传播角度增加了42% (从0.24°增加到0.34°).
- 裂传播范围一般在10毫米内,在下降负载光谱下观察到的最明显的迁移效应.
结论:
- 在现实的交通条件下,开发的框架准确地模拟了OSD中的疲劳裂传播.
- 横向负载位置显著影响应力强度因素和裂纹行为.
- 这些发现为现有钢桥甲板的疲劳和可靠性评估提供了重要的理论和技术支持.
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