锚胫侧倾角对拖曳锚在砂土中的下潜性能大变形数值分析

LARGE DEFORMATION NUMERICAL ANALYSIS ON THE EFFECT OF SPREADING ANGLE OF ANCHOR SHANK ON THE DIVING BEHAVIOR OF DRAG ANCHOR IN SAND

拖曳锚作为一种造价低、结构简单的系泊基础,在深海资源开发中得到了广泛的应用。拖曳锚的安装下潜性能与锚的自重、锚板厚度、锚胫与锚板夹角、土层条件等因素相关,锚胫对拖曳锚下潜性能的影响研究还不深入。提出了一种通过调整锚胫侧倾角来提高拖曳锚下潜性能的方法,并采用大变形有限元分析进行了验证。以MK5拖曳锚在砂土中的安装过程为例,分析了不同锚胫前倾角、锚胫侧倾角、拖曳锚密度、锚-土界面摩擦特性等因素对拖曳锚下潜深度的影响。结果表明,相较于传统的锚胫内倾的拖曳锚,拖曳锚锚胫直立以及向外侧倾斜时其嵌入深度有明显提高。

Drag anchors have been widely used as a mooring foundation with low cost and a simple structure.The installation and diving performance of the drag anchor is related to the anchor's weight,the thickness of the anchor fluke,the angle between the anchor shank and fluke,and the soil conditions.The influence of the geometric size of the anchor shank on the submersible performance of the drag anchor has not been studied deeply.A method to improve the diving performance of the drag anchor by adjusting the lateral angle of the anchor shank is proposed and verified by large deformation finite element analysis.Taking the installation process of MK5 drag anchor in sand as an example,the influence of different fluke-shank angle,lateral angle of anchor shank,anchor density,and anchor-soil interface friction characteristics on the diving depth of the drag anchor was analyzed.The results show that the embedded depth of the drag anchor shank is significantly improved when the shank is erect and leaned to the outside,compared with the traditional drag anchor with inwardly inclined anchor shank.