地基塌陷过程中埋地管线的有限元分析

地基塌陷往往影响埋地管线的正常使用和安全,针对这一课题,在室内模型箱试验的基础上采用Ansys软件建立有限元模型,应用单元生死技术模拟了土体塌陷范围不断扩大的过程,得出随着地基塌陷埋地管线内应力及沉降的变化过程曲线。通过与室内试验数据对比,证明了本数值模拟方法的可行性。进而又通过图像分析找出了管线的控制截面及控制力,并研究了埋地管线的壁厚和下卧层土体刚度在地基塌陷过程中对管线变形的影响规律,得到了一些具有工程实际意义的结论,为沉陷区域埋地管线设计和数值分析提供理论依据。

NUMERICAL ANALYSIS FOR INFLUNCE OF FOUNDATION COLLAPS ON BURIED PIPELINES

For the subject that foundation collapse often affects normal use and safety of buried pipelines,the software ANSYS is emploied to establish finite element model on the basis of indoor experiment of the box model in the paper.The graduatly enlarge process of the soil collapsing is simulated by using the technology of cell life and death.The stress vs. deflection curves of pipeline buried under the subsoil are drawn out as the soil collapses.The feasibility of the numerical simulation method is verified by comparison with the indoor test data.The control section and control force of the pipeline are identified by analysis of images.The tube wall thickness and soil stiffness are taken into account to analyze their influnce on the buried pipeline when the soil is collapsing.Finally some meaningful conclusions are drawed,which will be a base study on the design and numerical analysis of buried pipelines subjected to the settlement of the soil.