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地震断层引起的地面永久变形会导致穿越该断层的大口径埋地管道局部屈曲或整体失稳,使管道失效并退出服务。在该文中,对穿越逆断层的埋地管道屈曲稳定性进行了分析。将埋地管道及周围土体共同建立整体力学模型,分别以空间薄壳单元和实体单元模拟管道与土体介质,考虑管道与土体间的非线性接触行为,采用线性特征值屈曲分析方法及考虑非线性影响的Riks法分别研究了逆断层作用下的埋地管道的整体屈曲及局部屈曲行为。通过算例分析,给出了埋地管道发生屈曲时的临界载荷值及不同特征值对应的屈曲模态,发现特征值屈曲分析用于预测管道屈曲的载荷临界输入值是可行的。通过对钢管和PE管的分析,得到了管径、壁厚、断层倾角、土体剪切波速、管道埋深及管道-断层夹角等因素对埋地管道屈曲的影响。
Permanent ground deformation caused by seismic faults can lead to partial buckling or global instability of large-diameter buried pipelines crossing the fault, rendering the pipeline ineffective and withdrawn from service. In this paper, the buckling stability of buried pipelines passing through reverse faults is analyzed. The buried pipe and the surrounding soil together to establish the overall mechanical model, respectively, by the space shell element and the physical unit simulation pipeline and soil media, considering the pipeline and soil non-linear contact behavior, the use of linear eigenvalue buckling analysis and The Riks method, which considers the nonlinear effect, studies the global buckling and local buckling behavior of the buried pipeline under the action of reverse faults respectively. By the example analysis, the critical load values and the buckling modes corresponding to different eigenvalues of the buried pipelines are given. It is found that the eigenvalue buckling analysis is a feasible method for predicting the critical value of pipe buckling load. Through the analysis of steel pipe and PE pipe, the influence of pipe diameter, wall thickness, fault dip, soil shear wave velocity, pipe depth and pipe-fault angle on the buckling of buried pipe was obtained.