冲沟塌陷区输气管道的安全评价方法研究

为了判断管道的通行方案是否可行,以非线性接触模型为基础,应用ANSYS有限元软件,建立了悬空管段的三维管土相互作用模型,通过分析得出了悬空长度与最大Von Mises应力和沉降量之间的映射关系,二者均随悬空长度的增大而增大。根据应力分析结果选取了管道依次达到许用应力和屈服强度时的悬空长度作为临界指标,建立了悬空管道的安全评价模型,并以工程实例对其进行说明。结果表明:即使暴雨导致冲沟塌陷,该悬空管道仍处于安全状态,管道横穿该冲沟的通行方案是可行的。预期研究结果也可以为地质灾害区油气长输管道的安全运营与防护提供一定的技术支持。

Study on Method of Safety Assessment for Gas Pipelines in Gully Subsidence Areas

In order to judge whether the passage scheme of the pipeline is feasible,a three-dimensional pipe-soil interaction model was established by using ANSYS based on the non-linear contact model.By analyzing the model,the mapping relationship of the suspended length and the maximum Von Mises stress and settlement was set up.It showed that they both increased with the increase of suspended length.According to the stress analysis results,the safety assessment model of suspended pipeline was established by choosing the suspended length of allowable stress and yield stress as the critical index.By applying the model to practical case,the results show that even if the rainstorm causes the gully to collapse,the suspended pipeline was under safety operation status and that it is feasible for the pipeline to cross the gully.The proposed result can provide technical support for safety operation and protection of oil and gas pipeline in geological hazards areas.