半潜式钻井平台承载力极限状态设计

以半潜式钻井平台为研究对象,研究承载力极限状态设计方法的应用。文中首先介绍了承载力极限状态、分析方法、强度衡准;然后基于非线性软件ABAQUS,以加筋板架为研究对象,对其极限强度有限元数值仿真的分析方法、初始变形影响、结果分析技术等进行研究,总结形成数值仿真分析技术。在此基础上,分析半潜平台结构模型、载荷模型、边界约束等,研究目标平台在横向分离、纵剪、纵扭三种变形模式下的极限承载力及变形模式;分析等效模型、加筋模型对计算结果、计算效率的影响,提出半潜式平台极限强度工程化数值分析技术。最后,基于部分安全系数准则提出完整半潜式平台结构极限强度衡准,并对目标平台进行评估;总结形成半潜式钻井平台基于承载力极限状态的结构设计技术。

Structural design of a semi-submersible drilling platform in ultimate limit state

This paper carries out the research on the design of a semi-submersible drilling platform in the Ultimate Limit State (ULS). It firstly introduces the Ultimate Limit State (ULS), analysis the methods for the ultimate strength and the strength criteria. Then, the ultimate strength of a stiffened plate has been simulated by the nonlinear ifnite element package ABAQUS, and the numerical simulation analysis technologies are developed through the investigation of analysis methods, effects of initial delfection, results analytical technology, and so on. Furthermore, they are applied to analyze the structural models, load models and boundary conditions of the semi-submersible drilling platform, study the ultimate forces and damage modes of the target platform under the transverse split force, longitudinal shear force and longitudinal torsion, and research the effect of equivalent models and stiffened models on the results and computational effciency, in order to propose the engineering numerical analysis technologies for the ultimate strength of the semi-submersible platform. Finally, based on the partial safety-factor criterion, it puts forward the complete structure ultimate strength criteria for the semi-submersible platform and conducts the evaluation of the target platform, and concludes and proposes the structural design technology when it is in the ULS.