Parametric dependencies of the post-ultimate strength behavior of a ship’s hull girder in waves
Parametric dependencies of the post-ultimate strength behavior of a ship’s hull girder in waves
复制标题
DOI：
10.1007/s00773-012-0158-1
复制
发表时间：
2012-01
影响因子：
2.6
通讯作者：
Weijun Xu;K. Iijima;M. Fujikubo
中科院分区：
文献类型：
--
作者：
Weijun Xu;K. Iijima;M. Fujikubo
为了合理评估船体大梁倒塌的后果，有必要了解船体大梁的极限后强度行为，包括在极端波浪载荷作用下的整体变形和运动。在前面的研究中，作者提出了一个数值分析系统来预测波浪中的坍塌行为，包括极限后的强度行为。本文件的主要目的是以合理的方式澄清坍塌严重程度的参数相关性。这些参数可以包括与承载能力和极限载荷有关的参数。为此，推导了描述极限后强度行为的解析解。假定船体在倒塌过程中在船体中部形成塑性铰，整个船体模型为两个刚体系统，在船体中部通过一个非线性转动弹簧相互连接，反映了弯矩与转角之间的非线性关系。可以将该关系建模为分段线性曲线。进一步假定船体大梁的大运动和弹塑性变形不会影响载荷计算，并且船体大梁承受较大的单波。根据解析解，给出了预测坍塌严重程度的一些重要参数。
To rationally assess the consequence of a ship’s hull girder collapse, it is necessary to know the post-ultimate strength behavior of the hull girder including the global deformation and motions under extreme wave-induced loads. In the foregoing research, the authors proposed a numerical analysis system to predict the collapse behavior in waves including the post-ultimate strength behavior. The primary objective of the present paper is to clarify the parametric dependencies of the severity of the collapse in a rational manner. The parameters may include those related to load-carrying capacity and the extreme loads. To this end, an analytical solution to describe the post-ultimate strength behavior is derived. Assuming that a plastic hinge is formed at the midship during the collapse procedure, the whole ship is modeled as a two-rigid-bodies system connected to each other amidship via a nonlinear rotational spring, which represents the nonlinear relationship between the bending moment and the rotational angle. The relationship may be modeled as piece-wise linear curves. It is further assumed that large motions and elastic/plastic deformations of the hull girder may not affect the load evaluations, and that the hull girder is subjected to a large single wave. Some important parameters to predict the severity of the collapse are specified based on the analytical solution.