西南石油大学学报(自然科学版) ›› 2021, Vol. 43 ›› Issue (6): 62-70.DOI: 10.11885/j.issn.1674-5086.2020.10.22.01

• 力学专刊 • 上一篇    下一篇

高强钢丝蚀坑尺寸对应力集中效应的影响

吴梦雪, 尹力, 唐德发   

  1. 西南石油大学土木工程与测绘学院, 四川 成都 610500
  • 收稿日期:2020-10-22 发布日期:2022-01-08
  • 通讯作者: 尹力,E-mail:yl2863426710@163.com
  • 作者简介:吴梦雪,1987年生,女,汉族,四川乐山人,副教授,博士,主要从事风-车-桥耦合振动、钢结构腐蚀疲劳等方面的研究。E-mail:mx_swpu@126.com;尹力,1996年生,男,汉族,四川成都人,硕士研究生,主要从事建筑与土木工程研究。E-mail:yl2863426710@163.com;唐德发,1995年生,男,汉族,四川资阳人,硕士研究生,主要从事建筑与土木工程方面的研究工作。E-mail:Tdh_swpu@126.com
  • 基金资助:
    西南石油大学桥梁安全评估青年科技创新团队(2018CXTD07);工程结构安全评估与防灾技术四川省青年科技创新研究团队(2019JDTD0017)

Influence of Corrosion Pit Size on Stress Concentration of High Strength Steel Wire

WU Mengxue, YIN Li, TANG Defa   

  1. School of Civil Engineering and Geomatics, Southwest Petroleum University, Chengdu, Sichuan 610500, China
  • Received:2020-10-22 Published:2022-01-08

摘要: 斜拉桥拉索钢丝的力学性能对腐蚀极为敏感,腐蚀使钢丝表面产生的蚀坑会导致应力集中,削弱钢丝局部的疲劳抵抗能力,从而吸引疲劳裂纹从这里成核,这通常是斜拉桥拉索承载力和使用寿命降低的直接原因。为研究钢丝蚀坑尺寸的影响,基于数值模拟的方法,建立三维蚀坑模型来探讨蚀坑的长、宽、深对应力集中的影响。采用ANSYS建立高强钢丝的有限元实体模型,基于蚀坑的不同尺寸比例,即蚀坑深宽比、长宽比,模拟了深窄形和开放形蚀坑。通过有限元软件计算所得数据拟合出蚀坑尺寸因素与应力集中系数的曲线,根据所得曲线,拟合出蚀坑处应力集中系数随不同尺寸比变化的近似计算公式。基于蚀坑的应力分布图和应力集中系数随尺寸比的变化规律,探讨了蚀坑的长、宽、深对应力集中效应以及蚀坑处应力分布的影响,并横向比较了3个尺寸因素对应力集中效应的影响程度,结果表明,高强钢丝应力集中系数会随蚀坑深宽比或宽深比的增加而增加,而随蚀坑长度的增加而减小。此外,蚀坑长度的变化对高强钢丝应力集中系数的影响最为显著,蚀坑深度次之,而蚀坑宽度的影响最弱。

关键词: 锈蚀钢丝, 应力集中系数, 蚀坑, 参数分析, 有限元分析

Abstract: The mechanical properties of wires of cable-stayed bridges are extremely sensitive to corrosion. Corrosion pits on the surface of steel wires are caused by corrosion, which will lead to stress concentration and weaken local fatigue resistance of steel wires, and attract fatigue cracks to nucleate from here. This is usually the direct reason for the reduction of cable bearing capacity and service life of cable-stayed bridges. The influence of the length, width and depth of the pit on the stress concentration is discussed by means of numerical simulation. Firstly, a finite element model of a high-strength steel wire is established using finite element software ANSYS. Based on the different scale of pits, i.e. depth-width ratio and length-width ratio, the deep narrow and open pits are simulated. According to the data obtained by finite element calculation, the curve of the factors of pit size and stress concentration coefficient is fitted. According to the curve, the approximate calculation formula of stress concentration coefficient of semi-ellipsoid with different size ratio is established. Based on the stress distribution diagram of pits and the variation law of stress concentration coefficient with size ratio, the influences of length, width and depth of pits on stress concentration effect and stress distribution at pits are discussed, and the influences of three size factors on stress concentration effect are compared horizontally. The results show that the stress concentration coefficient of high-strength steel wire increases with the increase of the depth-width ratio or width-depth ratio of the corrosion pit, and decreases with its length. In addition, the variation of pit length has the most significant influence on the stress concentration coefficient of high-strength steel wire, followed by the pit depth and the pit width has the least influence.

Key words: corroded wires, stress concentration coefficient, corrosion pit, parametric analysis, finite element analysis

中图分类号: