摘要
为给含缺陷焊接管道脆性断裂的进一步研究提供基础,本文采用本征应变与局部应力相结合的方法模拟了两种典型的焊接残余应力,并计算了含内表面环向裂纹的管道分别在这两种残余应力作用下的应力强度因子K和裂尖约束应力T。计算结果表明:管道厚度方向的应力分布决定了裂纹根部的K-T值,沿着管道厚度呈拉应力分布的残余应力对应较大的K值与较小的T值,而沿着管道厚度总体呈弯曲分布的残余应力对应较小的K值与较大的T值;在残余应力分布和管道厚度都相同的条件下,管道内径对K-T值的影响随着裂纹深度的增大而加强。
By combining eigenstrain with local stress,two typical residual stresses for welded pressured pipeline are calculated and the K-T stresses for pipeline with internal circumferential cracks under these two residual stresses are simulated,respectively.Calculation results obtained show that residual stress distribution along pipeline depth determines K-T stresses of the deepest crack point,tensional residual stress along pipeline depth corresponds to bigger stress intensity factor K and weaker crack tip constraint T and bending residual stress along pipeline depth corresponds to smaller stress intensity factor K and stronger crack tip constraint T.Effects of pipeline radius on K Tstresses increase with larger crack length under the conditions of same residual stress distribution and pipeline depth.Results presented in this paper form the basis of the ongoing study to fragile fracture of welded pipelines.
出处
《应用力学学报》
CAS
CSCD
北大核心
2013年第2期251-256,306,共6页
Chinese Journal of Applied Mechanics
基金
大型先进压水堆核电站国家科技重大专项(2011ZX06002-010)
关键词
焊接压力管道
残余应力
本征应变
环向裂纹
裂尖约束应力
welded pressured pipeline,residual stress,eigenstrain,circumferential crack,crack tip constraint
