A Study on Ultimate Strength of Ship Hull Girder under Slamming

砰击作用下船体梁极限强度研究

基本信息

批准号：
10650904
负责人：
OKADA Hiroo
金额：
$ 2.3万
依托单位：
Osaka Prefecture University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650904/
关键词：
Stiffened plate panels FEM-aided Smith's method Ultimate collapse of ship hull girder Structural reliability Idealized structural unit method Progressive collapse Hydro-elasticity and or hydro-plasticity 船体縦曲げ強度水塊の衝突現象最終強度モンテラルロシミ

项目摘要

(1) First, this study deals with estimation methods for the ultimate strength and post ultimate behavior of ship stiffened plate structures under in-plane combined loads using finite element method considering elasto-plastic large deflection effects. Collapse mechanisms of stiffened structures are mainly classified into two collapse modes. One is the overall buckling mode, which means collapse of both stiffeners and panels. And another is local bucking mode, which means collapse of panels or stiffeners locally. To analyze these modes and their interactions, analyzed region is decided in this study. Satisfying the boundary continuity between adjacent structures under combined loads, Multi-freedom Dependent Constraint Method is applied for boundary condition.(2) Next, this study deals with collapsing behavior and reliability analysis of ship hull girder under longitudinal bending moment. A simplified estimation method is presented for collapsing behavior of ship hull girder under longitudinal bending by using Smith's method. Stress-strain curves of rectangular panels, which are used in Smith's method, are obtained from numerical database based on finite element method considering large deflection and elastic-plastic behavior. This method is applied to reliability analysis and statistical values such as standard deviation and reliability indexes are investigated by Monte Carlo simulation and sensitivity analysis.(3) Finally, a system is developed for collapsing behavior analysis of ship hull girders under extreme wave loads using a method combined with hydrodynamic force analysis and finite element analysis. The applicability of the system is also investigated through numerical examples applied to a basic box-type girder under extreme wave loads.

（1）首先，这项研究介绍了使用有限元方法在平面内组合载荷下使用弹性塑料大型偏转效应的有限元方法在平面内组合载荷下的最终强度和最终行为的估计方法。僵硬的结构的塌陷机制主要分为两种崩溃模式。一种是总体屈曲模式，这意味着加强剂和面板的崩溃。另一个是局部屈曲模式，这意味着面板或加强剂本地的崩溃。为了分析这些模式及其相互作用，在本研究中决定了分析的区域。在联合载荷下满足相邻结构之间的边界连续性，将多自由依赖的约束方法应用于边界条件。（2）接下来，本研究涉及纵向弯曲力矩下的船体船长的行为和可靠性分析。提出了一种简化的估计方法，用于使用史密斯的方法在纵向弯曲下的船体梁的崩溃行为。史密斯方法中使用的矩形面板的应力 - 应变曲线是根据数值数据库获得的，该数据库基于有限元方法，考虑到大偏转和弹性行为。该方法应用于可靠性分析，统计值（例如标准偏差和可靠性指数）通过蒙特卡洛模拟和灵敏度分析研究。（3）最后，开发了一种系统，用于使用与水力动力学力分析和有限元分析结合的方法，用于极端波载船体船体船体的行为分析。还通过在极端波负载下应用于基本盒子类型的基本木梁的数值示例研究了系统的适用性。