基于可靠度的海洋平台结构优化设计

【作者】 魏鹏；

【导师】 刘书田；

【作者基本信息】 大连理工大学 ， 工程力学， 2002， 硕士

【摘要】 桩基导管架海洋平台是海洋石油天然资源开发的基础性设施，是海上生产作业和生活的基地。目前，国内外对导管架平台结构系统的研究取得了一定的成果，但主要是静动力分析及安全评定，以及从确定性角度出发的优化设计。本文考虑了结构的随机性问题并在可靠性分析的基础上建立了结构的可靠性优化设计模型。应用大型有限元分析软件ANSYS提供的APDL语言接口，通过无需人工干预的参数化建模方法，建立了复杂结构的可靠度优化方法。实现了ANSYS与优化模块DOT(Design Optimization Tools)的对接，并通过具体的数值算例和现役胜利CB11F平台的分析优化，说明了这种优化方法是合理的，有效的，经济的。本项研究为海洋平台这一大型复杂结构的优化设计提供了新的思路和方法。各章节内容安排如下： 第一章首先介绍了海洋平台优化问题的工程背景和意义，然后综述了国内外在可靠度和基于可靠度的优化理论方面的研究进展，最后介绍了本文的主要研究工作。 第二章主要介绍了结构可靠度的基本理论，常用的计算方法，以及在应用过程中对原方法的改进。 第三章研究了基于可靠度的结构优化设计方法，包括基于可靠度的桁架结构拓扑优化和基于ANSYS二次开发的可靠度优化方法。通过算例验证了该方法的可行性与合理性并提出了该方法的一些不足及改进策略。 第四章建立了基于可靠度的海洋平台的结构优化设计模型，确立了随机参数模型，以胜利CB11F平台为例进行了基于可靠度的优化设计。算例结果显示了基于可靠度的优化是合理的，经济的。 第五章总结全文，并展望了进一步的研究工作。更多还原

【Abstract】 Offshore jacket platform is the foundational facility for offshore oil exploiting, and the base for marine producing and living. At present some achievements have been made on the -study of offshore jacket platform structure system. But the most of them are the static dynamical analysis, safety assessed and deterministic optimum design. In this paper, the uncertainty of the loads, geometry and materials of the structure are considered, and a model of reliability-based structural optimum design is established. A method no need of manual intervention for reliability optimization of complex structure is found by applying APDL language interface provided by ANSYS that is a large-scale software for finite element analysis. ANSYS and DOT (Design Optimization Tools) are jointed in this method. And it is showed reasonable, effective and economical via the numerical value and analysis of the optimization result of Shengli CB11F offshore platform. A new idea and method for the large reliability-based complicated structure optimum design is provided. As follows:In chapter 1, the engineering background and the meaning of optimization of offshore platform are presented. Sum up the research developments in domestic and abroad. In the last section, the brief description of the research in this dissertation is presented.In chapter 2, the basic theory and common computation method of structural reliability is given, and the improvement on original method in application.In chapters, reliability-based structure optimization design is investigated, including reliability-based truss structural topology optimization and two reliability optimization methods based on second development of ANSYS software. Numerical examples are given and the results indicate the validity and some shortages of these methods. Some reformative methods are raised.In chapter 4, a model with random parameter of reliability-based offshore platform structure optimization design method is established. The result of the reliability-based optimization of CB11F offshore platform in Shengli oil fields shows that the method is reasonable and economical.In chapter 5, the main contributions of the thesis is summarized and the further work is suggested.National Nature Science Foundation of China (No. 59895410) supports this thesis.更多还原