Abstract: In order to ensure the safe operation of buried natural gas pipeline (BNGP) under landslide debris flow (LDF), a model is established to investigate the strain characteristic of BNGP. The influence of longitudinal LDF morphology is analyzed for the elliptic deformation rate, tensile and compression strain of BNGP. The results show that the influence area of LDF is about 5m from the upstream and downstream position of active area, respectively. The peak value of elliptic deformation rate is mainly impacted by the thickness and length of LDF, and will increase linearly with that. The maximum value of axial strains will also increase linearly with length, thickness and breadth of LDF. It will decrease with the angle of mountain slope and depth of BNGP. The fracture failure of BNGP may be occurred at the active area of LDF and upstream position of that. But the local yield or fold failure of BNGP will be occurred at the active area of LDF and downstream position of that. At the same time, a method is proposed to estimate the maximum value of elliptic deformation rate and axial strains of BNGP under longitudinal LDF. The deviations between the prediction results and simulation data are less than ±10%.

中文翻译：

---

纵向滑坡泥石流作用下埋地天然气管道应变特性研究

摘要: 为确保滑坡泥石流（LDF）下埋地天然气管道（BNGP）的安全运行，建立模型研究BNGP的应变特性。分析了纵向LDF形貌对BNGP椭圆形变形率、拉伸和压缩应变的影响。结果表明，LDF的影响区域分别距活动区上下游位置约5m。椭圆形变形率的峰值主要受LDF厚度和长度的影响，并会随之线性增加。轴向应变的最大值也会随着 LDF 的长度、厚度和宽度线性增加。它会随着山坡角度和BNGP深度的增加而减小。BNGP的断裂失效可能发生在LDF的活动区及其上游位置。但BNGP的局部屈服或折叠失败将发生在LDF的活动区域及其下游位置。同时，提出了一种估算纵向LDF下BNGP椭圆形变形率和轴向应变最大值的方法。预测结果与模拟数据的偏差小于±10%。