【摘要】 基于三维虚拟裂纹闭合技术(3D-VCCT),利用大型有限元分析软件ANSYS对内表面含单条半椭圆裂纹的高压输气管道的应力强度因子进行计算,计算结果与已有结果具有相当好的一致性,并验证了该方法应用于薄壁管道计算的有效性。然后考虑了2条对称副裂纹的短半轴与长半轴的比值,主副裂纹的距离以及主副裂纹环向角度对主裂纹应力强度因子的影响,得到主裂纹应力强度因子的变化规律,并给出了主裂纹最深点和表面点应力强度因子的计算公式。提出的计算方法和结果对高压埋地输气管道的风险评估、设计和施工具有一定的参考价值。更多还原

【Abstract】 The stress intensity factor for high pressure gas pipeline with single surface crack of an elliptical front was evaluated by the method of three-dimensional virtual crack closure technique(3D-VCCT) and the finite element method(FEM).Quantitative comparisons were made between the calculated results and the existing results,which showed great agreement.Then,two symmetric minor cracks were placed in the structure,and the shape of the minor crack,and the length and angle between the minor and the main cracks were considered to study the effects on the stress intensity factors of the main crack.Finally the rule and formula of the stress intensity factor of the main crack were obtained.The developed numerical simulation method and conclusion may provide some references for the risk evaluation,design and construction of high pressure buried gas pipeline.更多还原