基于材料塑性失效准则的内缺陷参数对管柱剩余抗拉强度影响分析

Analysis of the Influence of Internal Defect Parameters on the Remaining Tensile Strength of Pipe Columns Based on Material Plastic Failure Criteria

摘要: 目前主要在材料弹性范围内研究含缺陷管柱剩余强度，较少定量分析不同缺陷尺寸参数对剩余抗拉强度的影响规律。基于材料塑性破坏准则，采用有限元数值模拟方法，结合正交试验设计，分析了拉伸载荷下缺陷管柱应力分布规律，研究了内腐蚀缺陷长度、宽度、深度、管柱外径、径厚比等参数对管柱剩余抗拉强度的影响规律。结果表明：缺陷管柱无因次抗拉强度随缺陷深度增加呈二次曲线关系降低，随缺陷长度的增加呈指数关系逐渐变大，随缺陷宽度增加呈指数关系逐渐减小，随套管径厚比增加呈线性关系减小。缺陷深度与宽度对无因次抗拉强度有显著影响，总体上两者影响程度基本相当；缺陷长度对无因次强度有一定的影响，管柱径厚比对无因次强度影响较小，而管柱外径影响极小。基于数值分析结果，建立了含缺陷管柱无因次抗拉强度多因素预测方法，为工程上含缺陷管柱强度评价提供参考。

Abstract: At present, the research mainly focuses on the residual strength of defective pipe columns within the elastic range of materials, and there is relatively little quantitative analysis of the influence of different defect size parameters on the residual tensile strength. Based on the material plastic failure criterion, finite element numerical simulation method was adopted, combined with orthogonal experimental design, to analyze the stress distribution law of defective pipe columns under tensile load. The influence of parameters such as internal corrosion defect length, width, depth, pipe outer diameter, and diameter thickness ratio on the residual tensile strength of pipe columns was studied. The results indicate that the dimensionless tensile strength of defective pipe columns decreases in a quadratic relationship with increasing defect depth, gradually increases exponentially with increasing defect length, decreases exponentially with increasing defect width, and decreases linearly with increasing sleeve diameter to thickness ratio. The depth and width of defects have a significant impact on the dimensionless tensile strength, and overall, the degree of influence of the two is basically equivalent. The defect length has a certain impact on the dimensionless strength, and the ratio of pipe diameter to thickness has a small effect on the dimensionless strength, while the effect of pipe outer diameter is minimal. Based on numerical analysis results, a multi-factor prediction method for dimensionless tensile strength of defective pipe columns was established, providing reference for strength evaluation of defective pipe columns in engineering.