MARS2000User’s guide
Booklet 2
DEFINITION OF A SECTION
剖面定义
TABLE OF CONTENTS目录
Chapter 1 : GENERAL COMMENTS概述 (1)
Chapter 2 : MAIN SECTION DATA主要剖面数据 (3)
Chapter 3 : SECTION GEOMETRY剖面几何形状 (8)
Chapter 4 : COMPARTMENTS AND LOADS分舱和载荷 (24)
Chapter 5 : FATIGUE疲劳 (29)
Chapter 6 : GENERAL FEATURES特 (30)
Chapter 1 : GENERAL COMMENTS概述
1.1    INTRODUCTION说明
MarsIn allows the input of any section along the ship length. The section is described by:
•  Longitudinal elements contributing to the hull girder strength.纵向型材
•  Transverse stiffeners.横向型材
•  Compartments分舱
1.2    MARSIN INTERFACE界面
The module allowing to input the data of a section is organized around the following application:
Figure 1: MARSIN
Warning Box: displays warning message when MARSIN detects incoherence in the Section definition.
Section view: displays a view of the section.
1.3    A GOOD WAY TO MODELISE A SECTION剖面创建
The geometry of a section is panel oriented: the section has to be divided into several panels, each
one corresponding to a physical entity such as the outside shell, the strength deck, the inner bottom or a 分别创建几个剖面，每一个具有独立的实体（如外板、甲板、内底、纵向壁）Each panel is made of contiguous segments described by two nodes. Those segments have
eventually different geometry (straight, circular or corrugated line).每个剖面板两个节点定义线段，这些线
段可以具有不同的几何特性（外板，圆或波形）
The way of the description defines a direction on the panel. This direction is commonly used to define flange direction 还有方向定义（主要对于纵向折边）
Each panel is an independent entity, even for calculation.每个剖面板可单独计算
Once the panels are fully described, welding joints and longitudinal stiffeners (with their scantling) can be located.一旦剖面板定义完成，可以进行焊接点和纵向型材的定义
If necessary, it is also possible to define transverse stiffening zones.若需要还可进行横向型材的定义
1.4    MAIN DIFFERENCES WITH MARSWIN特
1.4.1        Compartments data分舱数据（不同的剖面）
A new data has been added: main destination of the compartment. This data leads to the evaluation of net scantling of the section.增加新的数据来说明分舱，已计算净构件规格
The top of air pipe is replaced by the deck level to which the air pipe extends.可用透气管头代替甲板When openning an old MarsWin database, those data are initialized：当老的数据打开时，要初始定义以下参数
•  For the main destination: on the basis of the compartment load type. It should be checked carefully.定义载荷类型
•  For the air deck: minimum between the top of air pipe and the depth at strength deck.定义空气管高
1.4.2        Span跨距
The SpanS value is recovered through the Spacing of primary transverse structure (see 3.3 and
3.8)." 主要横向构件跨距
The SpanL value is recovered through the stiffeners span reduction.型材跨距
Chapter 2 : MAIN SECTION DATA主要剖面数据
On the Section menu, click on Main Data - Moments (Figure 46) to display the Main Section Data Window.
2.1    MAIN DATA主要数据（第一个表）
The first tab of the main section data window allows defining the X longitudinal location of the section and also to precise main data that might be dependent of this location.
Moreover it allows defining the type of section (e.g. Half section, Full section, Thin walled structure).
Figure 2: MAIN DATA WINDOW
The Default (BSD) button of this window initializes the Main Data with the values already defined in the Basic Ship Data or with default values. It is only an initialization: a change in the Basic Ship Data does
n’t modify the Main Section Data按钮BSD数据见外板和基本船舶数据，
It initializes：初步确定
•  Identification = Midship section中剖面
•  Longitudinal Location (from APP) = Scantling length / 2纵向位置（船长中点）
•  Extension heights = 0.000 m延伸高度
•  All the others data are initialized with their BSD equivalent.其他的数据见外板和基本船舶数据
Extension heights (in m): used to define the zone in which the materials are defined.
Figure 3: EXTENSION HEIGHTS
2.2    STRENGTH强度（第二个表）
The second tab of the main section data window allows entering the design values of the still water bending moments at X, still water shear force and vertical wave bending moments.沿纵向静水弯矩If you prefer don’t enter a SWBM（静水弯矩） value for a section, the calculations are based on: 如果没有输入静水弯矩值给剖面，会按以下计算
•  The values defined in the BSD taken as midship section values and modified using the rule distribution law.按BSD基本船舶数据定义值并按相关规则修改
•  If no value has been defined in the BSD, the rule distribution will be applied to the admissible rule
values.如果没有BSD基本船舶数据定义值，则按规范分配的容许值。
Figure 4: STRENGTH WINDOW
The ship behavior defined in the BSD (both hogging/sagging, hogging only, sagging only) is displayed on screen. Obviously, it can not be corrected at this level.
在BSD基本船舶数据定义的中拱/中垂，中拱，中垂，可能是不正确的。
The rule calculations are based on rule values of vertical wave bending moments automatically
calculated by the program.软件是自动按垂向波浪弯矩计算的。
However it is possible to perform special calculations with vertical wave bending moments defined by the user. If so, it is reminded that the obtained results are not according to the rules.
无论如何，可以由用户来定义。
2.3    FATIGUE疲劳强度（第三个表）
The third tab of the main section data window allows defining the data needed for fatigue calculation.
This tab allows precising:
Figure 5: FATIGUE DATA WINDOW
•  Mean weld toe angle for butt joints ( 30° default value )
•  Mean weld toe angle for T joints and cruciform joints ( 45° default value )
On this tab (Figure 5), the Weld configuration button shows a window which allows to initialize the lambda (λ) value:
Figure 6: WELD CONFIGURATION WINDOW
2.4    SHIP STATE船状态（第四个表）delete in
The fourth tab of the main section data window allows defining the Ship State.
Figure 7: SHIP STATE WINDOW
The State type can be:
•  Project项目规划
•  As Built在建
•  Survey检验