轴向腐蚀缺陷宽度对管道极限内压荷载的影响

针对海底管道的中高强度钢腐蚀极限内压预测问题，采用有限元弹塑性分析方法，考虑材料非线性和几何非线性，建立非线性分析模型并与试验数据进行对比分析，验证了有限元模型的合理性和准确性。基于有限元计算结果分析得出腐蚀深度、腐蚀长度及腐蚀宽度对海底管道极限内压的影响，并回归得到了适用于轴向腐蚀管道极限荷载的计算公式。通过与腐蚀管道爆破试验数据和现有腐蚀管道计算方法的比较分析，验证了该方法能够得到较准确的结果，可为海底腐蚀管道在内压荷载作用下的评估提供一定的依据。

Impacts of axial corrosion width on ultimate internal pressure load of pipeline

To predict the ultimate internal pressure of subsea pipelines in case of meditium/high-strength steel corrosion, a plastic finite element analysis is made. Besides, considering the nonlinearity and geometric nonlinearity of materials, the nonlinear analysis model is built and the modeling results are compared with the experimental data to verify if the finite element model is reasonable and accurate. On this basis, the impacts of corrosion depth, length and width on ultimate internal pressure are obtained. The formula for ultimate load of pipelines with axial corrosion is also gained by regression. Compared with the burst test data of corrosion pipes and existing corrosion calculation methods, it is proved that this method can provide more accurate results, which will be used as a basis for assessing subsea corrosion pipelines under internal pressure loads.