拉应力作用下含缺陷埋地管道应变与裂纹扩展行为分析  

Behavior analysis on strain and crack propagation of buried pipeline containing defects under tensile stress

作　　者：朱仁迟 朱豪豪 郭海林[1] ZHU Renchi;ZHU Haohao;GUO Hailin(Faculty of Engineering,China University of Geosciences,Wuhan,Hubei 430074,China)

机构地区：[1]中国地质大学工程学院,湖北武汉430074

出　　处：《福州大学学报（自然科学版）》2022年第4期553-559,共7页Journal of Fuzhou University(Natural Science Edition)

基　　金：湖北省安全生产专项资金科技项目(鄂应急办[2020]12号)。

摘　　要：采用数值模拟和宽板拉伸实验相结合的方法,研究单点缺陷与双点缺陷对含螺旋焊缝缺陷管道应力应变及裂纹扩展行为.基于管材的力学性能和标准等确定缺陷尺寸位置参数,利用ABAQUS建立含不同参数缺陷的宽板及全尺寸管道模型分析拉外力下的应力分布特点,研究不同缺陷长度与深度对管道焊缝处裂纹萌生的规律;设计3组含焊缝处缺陷管道宽板拉伸实验,研究管道应变与裂纹扩展情况.结果表明:拉应力下管道宽板模型具有可靠性;随着缺陷尺寸的增大,相对长度为0.79、相对深度为45.98的缺陷对裂纹萌生影响最大.对比宽板试验发现,宽板焊缝上、下侧截面点位的应力应变在轴向拉力作用下,均呈现出先缓慢增加后快速上升的趋势,且相对单点缺陷,双点缺陷的相互作用对裂纹的萌生和扩展产生较大影响.Numerical simulation and wide-plate tensile experiments are used to study the stress-strain and crack propagation behaviors of single-point defect and double-point defect on pipelines with spiral weld defects.Determine the defect size and location parameters based on the mechanical properties and standards of the pipe.Using ABAQUS,a wide plate and full-size pipeline model with defects with different parameters was established to analyze the stress distribution characteristics under tensile external force,and to study the regularity of crack initiation at the pipeline weld with different defect lengths and depths.In addition,three groups of wide-plate tensile experiments of pipelines with defects at welds are designed to study the strain and crack propagation of pipelines.The results show that the pipe wide plate model is reliable under tensile stress.As the defect size increases,the defect with a relative length of 0.79 and a relative depth of 45.98 has the greatest impact on crack initiation.Compared with the wide plate test,it is found that the stress and strain at the upper and lower crosssection points of the wide plate weld show a trend of slow increase at first and then a rapid increase under the action of axial tension,and compared with single-point defects,the interaction of doublepoint defects has a greater impact on the initiation and propagation of cracks.

关 键 词：焊缝缺陷 宽板拉伸实验 裂纹扩展 应力应变 数值模拟 管道焊接 

分 类 号：U175.3[交通运输工程] TE973[石油与天然气工程—石油机械设备]