浮力装置触发深海管道水平向整体屈曲效果的数值模拟研究

海洋油气资源的运输主要通过海底管道进行,管道在工作时受到较大的温度荷载,会产生整体屈曲变形。深海管道设计中常采用人为装置触发一定程度的水平向整体屈曲变形,来释放轴向的温度应力,浮力装置是常用的触发方式之一。本文通过数值模拟研究,分析了不同浮力大小和不同浮力施加范围下,管道水平向整体屈曲的临界屈曲力,得出临界屈曲力随浮力大小和施加范围变化的情况;并研究了不同土体阻力下,浮力装置触发整体屈曲的效果。研究表明,水平向土体阻力较大时,浮力装置触发水平向整体屈曲的效果较好。浮力装置的触发效果对轴向土体阻力不敏感。

Numerical study on the lateral global buckling of the triggering effect of buoyancy devices on the deep sea pipeline

Pipelines are widely used in offshore oil exploitation engineering practice for transportation. Pipelines exhibits large temperature load in operation, and experiences lateral global buckling deformation. In order to avoid random global buckling and control buckling deformation, trigger devices are installed to generate a controllable lateral buckling deformation, reducing axial compressive stress caused by temperature load. Buoyancy device is one of the effective trigger devices. The effect of buoyancy devices on influencing lateral buckling are analyzed with numerical simulation method in this paper. Sensitivity analysis have been considered to reveal the impact of key parameters (magnitude of buoyancy load and applying range of buoyancy load) on buckling process. The variation of critical buckling force of pipelines with different key parameter combinations are calculated. The performance of buoyancy devices on protecting pipelines under different soil resist ancelevels are also checked. Results show that pipeline laying on high lateral soil resistance seabed benefits more from installing buoyancy devices in lateral buckling process. Axial soil resistance has little influence on the performances of buoyancy devices.