﻿ 总纵弯矩作用下的船体结构极限承载力分析
 舰船科学技术  2023, Vol. 45 Issue (7): 22-25    DOI: 10.3404/j.issn.1672-7649.2023.07.005 PDF

Analysis of ultimate bearing capacity of hull structure under total longitudinal bending moment
CHE Jin-zhi
Shanxi College of Applied Science and Technology, College of Architectural Engineering, Taiyuan 030062, China
Abstract: The safety of ship navigation is one of the key issues in the field of navigation. The value of the total longitudinal bending moment of the hull will change under different circumstances. The study of the ultimate bearing capacity of the hull structure in this case is the key to the safe navigation of ships. Therefore, the ultimate bearing capacity analysis method of the hull structure under the action of the total longitudinal bending moment is proposed. This method uses the finite element software to establish the hull structure model, and calculates the total longitudinal bending moment of the hull structure. Based on it, the ultimate bearing capacity of the structure is calculated from the angle of the ultimate deflection bearing capacity of the hull beam structure and the balance of the hull section, and the multi-angle analysis is carried out under the finite element environment. The experimental results show that this method can effectively build the finite element model of the hull structure, and effectively analyze the distribution of the ultimate bearing capacity of the hull structure deflection and the ultimate bearing capacity of the mid-section structure under different total longitudinal bending moments of the hull structure. The application effect is remarkable.
Key words: total longitudinal bending moment     hull structure     ultimate bearing capacity     bending deformation     finite element     equilibrium equation
0 引　言

1 船体结构的极限承载力分析方法 1.1 船体结构有限元模型构建

 图 1 船体结构有限元模型构建流程示意图 Fig. 1 Schematic diagram of building process of finite element model of hull structure
1.2 船体结构总纵弯矩计算方法

 ${W_i} = {I_i} \cdot \sum\limits_{i = 1}^n {{\zeta _i}{A_i}}。$ (1)

 ${\zeta _i} = {\zeta _i}({\varepsilon _i})，$ (2)

 ${\varepsilon _i} = \phi ({y_i} - {y_0}) 。$ (3)

 $g(t) = {\sigma _i}{W_i}{A_i} - {Q_{st}} - {Q_{wt}} = 0。$ (4)

1.3 船体结构的极限承载力分析模型

 $y'' = \frac{{ - g(t)}}{{EI}} 。$ (5)

 ${y_{i + 1}} - 2{y_i} + {y_{i - 1}} = - {s^2}\frac{{g(t)}}{{E{I_i}}}。$ (6)

$\Delta {\kappa _H}$ 为水平曲率增量， $\Delta {\kappa _V}$ 为纵向曲率增量， $\Delta {M_H}$ 为船体结构水平弯矩增量，构建总纵弯矩下，船体结构剖面平衡方程如下：

 $\left\{ \begin{gathered} \Delta {M_H} \\ \Delta {M_V} \\ \end{gathered} \right\} = \left\{ \begin{gathered} {R_H}{R_{HV}} \\ {R_{HV}}{R_V} \\ \end{gathered} \right\}\left\{ \begin{gathered} \Delta {\kappa _H} \\ \Delta {\kappa _V} \\ \end{gathered} \right\}g(t)，$ (7)
 ${R_H} = \sum {{{(E{U_e})}_i}} \sum {(y_i^2 - y_G^2)}，$ (8)
 ${R_V} = \sum {{{(E{U_e})}_i}} \sum {(z_i^2 - z_G^2)} ，$ (9)
 ${R_{HV}} = \sum {{{(E{U_e})}_i}} \sum {(z_i^2 - z_G^2)} (y_i^2 - y_G^2) 。$ (10)

 ${U_e} = U'\eta。$ (11)

 $\eta = \frac{{\bar \zeta }}{{\bar \varepsilon }}$ (12)

2 仿真分析

 图 2 船舶有限元模型 Fig. 2 Finite element model of ship

 图 3 不同总纵弯矩情况下船体结构单元平均应力变化趋势 Fig. 3 Change trend of average stress of hull structural elements under different total longitudinal bending moments

 图 4 船体结构中截面剖面极限承载力分布图 Fig. 4 Distribution diagram of ultimate bearing capacity of section in hull structure

 图 5 总纵弯矩与船体结构挠度承载力拟合曲线 Fig. 5 Fitting curve of total longitudinal bending moment and hull structure deflection bearing capacity
3 结　语

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