User Guide for GStab *

1. Essentials *

1.1 Pop-up (context) menus *

1.2 Zooming *

1.3 Multiple selection *

1.4 Copy & Paste *

1.5 Print *

1.6 Docking windows *

2. Workspace *

2.1 General description *

2.2 Conditions Tab *

2.3 Loading (Compartment Groups) Tab *

2.4 Damage Cases Tab *

2.4.1 Defining damage cases *

2.4.2 Analysing Damage Cases *

2.4.3 Defining and working with damage case sets *

2.4.4 Viewing and analysing the results of the damage stability calculations *

2.5 Design Database Tab *

 

 

User Guide for GStab

1. Essentials

1.1 Pop-up (context) menus

GStab supports the pop-up menus introduced by Windows 95. Its diagrams, spreadsheets, Workspace panes and Graphics panes have a pop-up menu with frequently used commands associated with the current context. These menus are also referred to as context menus.

 

To display the pop-up menu for an object (such as a column in the spreadsheet or a compartment in the Graphics section pane), click the right mouse button inside the object.

1.2 Zooming

The panes of the Graphics window and all the diagrams (except for the one in the Criteria View) support zooming.

 

To zoom

1. Press CTRL, and hold down left mouse button.

  1. Drag mouse to select the zoom area and release the mouse button.

To reset zooming

Press CTRL, and double-click in the zoom area.

1.3 Multiple selection

GStab supports multiple selection:

 

In tree views and multiple selection list boxes, you can select several items; in spreadsheets - several rows; in the Section pane of the Graphics window – several compartments.

 

To make a multiple selection use the buttons CTRL and SHIFT according to the Windows 95 standard.

 

NOTE: In the Graphics window, CTRL is used for zooming, therefor only the SHIFT button is used to make multiple selection.

1.4 Copy & Paste

GStab’s support for Copy & Paste can be very useful in creating a custom report.

 

To copy a table, a diagram or one of the panes of the Graphics window, select the Copy option in the context menu. The copied object will be placed on the Clipboard. It can then be pasted into another program such as MS Word, Word Perfect or any other program that supports Clipboard.

    1. Print

To print a table, a diagram or one of the panes of the Graphics window, select the Print option in the context menu.

1.6 Docking windows

The Workspace window and the Graphics window behave like docking windows. Docking windows have two display modes: floating or docked. In floating mode, a window has a thin title bar and can appear anywhere on your screen. A floating window is always on top of all other windows. In docked mode, a window is fixed to a dock along any of the four borders of the main GStab window.

 

To show or hide a docking window

Click the name of the window in the View/More... menu or the corresponding button on the main toolbar.

To change a docked window to a floating window

Double-click in the window border.

To dock a floating window

Double-click the window title bar to return the window to its previous docked location, or point to the title bar and drag the window to a different dock area.

To position a floating window over a dock (without docking it)

  1. Point to the title bar of the window.
  2. Hold down the CTRL key and drag the window over any dock area of the application window.

 

 

2. Workspace

2.1 General description

GStab uses workspace to help you organise your project, its elements, and your preferences for how project information appears on your screen. Within the workspace, you can work with following elements of the currently open project:

 

Tabs at the top of the workspace window provide quick access to different views of your project. These views are used not only to display and browse, but also to create, modify, reorganise and operate the displayed elements. The following activities can be carried out in these views:

 

2.2 Conditions Tab

The Condition Tab provides access to the condition tree, where you can work with the project’s existing conditions. The conditions are automatically added to the Condition Tree on saving. The ‘File/Save As’ option or corresponding Toolbar button should be used to save the current condition with a new name. This name will appear in the condition tree. The currently active condition is shown in bold style.

 

To load a condition

Select the condition. In the context menu, click

Set As Active condition.

Alternatively, double-click the condition name.

To view and edit condition properties

Select the condition; in the context menu, click the option Condition Properties.

To view and compare details of several conditions

Select one or several conditions (hold CTRL or SHIFT to make a multiple selection). In the context menu, click Condition Summaries or Stability curves to open the Conditions View. The contents of the Conditions View will always correspond to the selection in the workspace.

To delete conditions from the condition tree

  1. Select one or several conditions (hold CTRL or SHIFT to make a multiple selection).
  2. Press Delete.

 

NOTE: Deleting a condition as described above, removes it from the condition tree only, without deleting the condition file. To delete the condition file, use Windows File Explorer.

To load, save or create a new condition tree file

In the context menu, click on one of the File options. The default extension of a condition tree file is ‘ctr’.

 

    1. Loading (Compartment Groups) Tab

The Loading Tab provides access to the compartment groups defined for the project. GStab automatically generates following three compartment groups:

In addition to the compartment groups generated by GStab, the user can create an unlimited number of custom groups. To minimise the effort in organising the custom groups, there is a facility of creating folders. The new groups will be automatically placed into the active folder.

 

To create a new folder

In the context menu, click New Folder. A new folder will be created in the selected folder or, if none selected, at the root of the tree. It will be set as the active folder and all the new groups will be placed there automatically.

To create a new compartment group

  1. In the Graphics window, select the compartments (for multiple selection, hold SHIFT).
  2. In the context menu for the Section pane of the Graphics window, select Create Group.
  3. In the appeared ‘New Compartment Group’ dialog box, enter the name and press OK. The compartment group will be added to the active folder.

To change the state or loading of compartments

  1. In the Workspace window, select the compartments and/or groups of compartments.
  2. In the context menu, select:
    • Load ...to open the ‘Load and Pressure Control’ dialog box, where the load and the pressure control of the compartment can be changed. In the dialog box, one cell can be modified at a time.
    • Fullto fill the compartment to the maximum extent
    • Flood – to change the state of the compartment to FREE FLOODED
    • Recoverto recover a free-flooded or entrained compartment, its state will set to INTACT
    • Damage... – to open the ‘Damaged Compartment’ dialog box, where the extent of the damage for the selected compartment can be specified. It is used in the outflow calculations performed from the Outflow view. The state of the compartment is changed to ENTRAINED.

To change the compartment name format

  1. In the context menu for the workspace, select Properties.
  2. In the ‘Tree properties’ dialog box, select the option of how the compartment name will appear in the tree and press OK.

To load, save or create a new compartment groups file

In the context menu, click on one of the File options. The default extension of a compartment groups file is ‘ltr’.

    1. Damage Cases Tab
      1. Defining damage cases

The damage case are defined directly in the Graphics window and stored in the Database. The existing damage cases can be accessed from the workspace.

 

Colours used to represent damage case compartments:

 

To view and edit the properties of the damage cases

  1. In the context menu, select Damage Case Properties. The Damage Case view will appear. The contents of this view will always correspond to the selection in the workspace. In Damage Case view, you can specify following parameters:
  • criteria set
  • number of flooding stages
  • first stage of flooding
  • permeability to be used instead of the default one

To create a Starboard, Portside or Bottom damage case for the damage length according to the regulations

  1. In the Workspace, press one of the buttons SB, PS or Bottom. The marker bar in the Graphics window will have a shape of an ‘H’, which represents the damage length.
  2. In the Graphics window, place the damage length by moving the marker ‘H’. The damage case according to the location of the damage length will be automatically generated and highlighted in the graphics.
  3. In the context menu for the graphics window, click Add Damage Case. The damage case will be added to the All Damage Cases folder in the workspace. Its name will be generated from the position and type of the damage. All the damaged compartments will be considered to have a single free surface (to define several free surfaces see the topic ‘Grouping compartments with respect to single free surfaces’).

 

The number of damage case you can create is unlimited.

To create a custom damage case

  1. In the Workspace, press the button Manual. The marker in the Graphics window will have a shape of a bar to indicate the position of the section.
  2. In the Graphics window, select the damaged compartments. To select a compartment, place the section by moving the marker bar, then click on the compartment to select. To select several compartments, hold SHIFT.
  3. In the context menu for the graphics window, click Add Damage Case. You will be prompted to specify the name for the damage case. The damage case will be added to the All Damage Cases folder in the workspace. All the damaged compartments will be considered to have a single free surface (to define several free surfaces see the topic ‘Grouping compartments with respect to single free surfaces’).

 

The number of damage case you can create is unlimited.

 

 

To add or edit cross-flooded compartments

You can add cross-flooded compartments to any existing damage case. Once you’ve finished editing the damage case with respect to the cross-flooded compartments, they are considered to have a single free surface (to define several free surfaces see the topic ‘Grouping compartments with respect to single free surfaces’). These are the steps to follow:

 

  1. In the Workspace, select the damage case. The selection will be reflected in the Graphics window.
  2. In the Workspace, press the button Cross. The marker in the Graphics window will have a shape of a bar to indicate the position of the section.
  3. In the Graphics window, position the section by moving the marker bar, and select the compartments to be excluded. Clicking on a selected compartment deselects it.

 

The changes you make are automatically stored in the database and reflected in the Workspace tree and the Damage Case view.

Grouping compartments with respect to single free surfaces

Once you’ve defined a damage case following the steps described above, it will comprise two compartment groups at most, "Primary 1" and, if you added cross-flooded compartments, "Cross 1", each group representing a single free surface. To group the compartments within these groups in order to specify several free surfaces, follow these steps:

 

  1. In the Workspace, select the damage case. The selection will be reflected in the Graphics window.
  2. In the Workspace, press the button Single Free S’face Group. The marker in the Graphics window will have a shape of a bar to indicate the position of the section.
  3. In the Graphics window, position the section by moving the marker bar, and select the compartments to be grouped. Clicking on a selected compartment deselects it.
  4. In the context menu for the graphics window, click Group. The selected compartments will be placed in one group.

 

A particular compartment can’t be found in several groups. Placed in a new group, it will be automatically removed from the group it previously belonged to.

 

 

To create a lesser extent damage case

The lesser extent damage cases are derived from the existing damage cases. The procedure is as follows:

 

  1. Create a copy of the original maximum extent damage case
  2. Edit the copy of the damage case with respect to which of the originally damaged compartments should be excluded.

 

The number of lesser extent damage case you can derive from one particular damage case is unlimited. These are the steps you should follow:

 

  1. In the Workspace, select the original maximum extent damage case. The selection will be reflected in the Graphics window.
  2. In the context menu for the selected damage case, click Copy As Less Extent. A new damage case will be added to the All Damage Cases folder. Its name will consist of the name of the original damage case and the appendix ‘Less 1(2,3,4...)’.
  3. In the Workspace, press the button Less Extent. The marker in the Graphics window will have a shape of a bar to indicate the position of the section.
  4. In the Graphics window, position the section by moving the marker bar, and select the compartments to be excluded. Clicking on a selected compartment deselects it.

 

The changes you make are automatically stored in the database and reflected in the Workspace tree and the Damage Case view.

To change the compartment name format

  1. In the context menu for the workspace, select Properties.
  2. In the appeared ‘Tree properties’ dialog box, select the option of how the compartment name will appear in the tree and press OK.
      1. Analysing Damage Cases

Once created, a damage case can be applied to the current condition or evaluated with respect to the related criteria set.

 

To apply a damage case to the current condition.

  1. In the Workspace, select a damage case. The selection will be reflected in the Graphics window.
  2. In the context menu for the selected damage case, click Apply to Current Condition.
  3. In the appeared Flooding Stage dialog, choose the stage to be applied and press OK. The Flooding Stage dialog will not appear, if there is only one flooding stage, it will be applied directly.

 

The current condition will be changed with respect to the applied damage case. It can then be analysed in all the views related to the currently active condition.

To evaluate a damage case with respect to a criteria set.

  1. In the View menu, click Criteria Evaluation to open the Criteria Evaluation View.
  2. In the Workspace, select a damage case. The selection will be reflected in the Graphics window.
  3. In the Criteria Evaluation view, check the Apply damage case check box. The damage case will be evaluated according to the specified criteria set. The results can then be studied in the Criteria Evaluation view for the most critical stage. The most critical stage is shown next to the damage case name. (To view the results for all the stages use the Damage Results view.)
  4. In the appeared Flooding Stage dialog, choose the stage to be applied and press OK. The Flooding Stage dialog will not appear in case there is only one flooding stage, the final stage will be applied directly.

 

Applying a damage case in the Criteria Evaluation view does not affect the current condition. It only affects the information in the Criteria view.

 

      1. Defining and working with damage case sets

The damage case sets can be used:

 

To create a new damage case set.

  1. In the Workspace, select the damage cases and the existing damage case sets to be added to the new damage case set.
  2. In the context menu, click Create set.
  3. In the appeared ‘New Damage Case Set’ dialog, specify the name of the new damage case set and press OK. The new damage case set will be added to the workspace.

 

NOTE: A damage case set contains references to the damage cases in the All Damage Cases folder. You can edit properties of a damage case from within any damage case set that references it.

To delete damage cases.

  1. In the Workspace, select the damage case to be deleted. You can also select several damage cases.
  2. Press Delete.

 

NOTE: Deleting a damage case from a damage case set other than ‘All Damage Cases’ does not delete the damage case from the database, it only removes its reference from this particular damage case set.

Deleting a damage case from the ‘All Damage Cases’ folder deletes it from the database and removes its reference from all the damage case sets. To avoid misunderstanding, different symbols are used:

- damage case (in the All Damage Case folder)

- references to a damage case (in damage case sets)

To perform damage stability calculations for a damage case set.

  1. In the Workspace, select the damage case set.
  2. In the context menu, click
    1. Apply to the CURRENT condition
    2. Apply to a SET of conditions
    3. Apply to a RANGE of conditions
  1. In the appeared ‘Calculations for Damage Case Set’ dialog, set up the parameters for the calculations and press the Start button.
  2. In the appeared ‘Save as’ dialog, specify the name of the output file and press OK. The calculation will proceed. The gauge will indicate the progress of the calculation process. When the calculation is done, a notification message will appear. Once the calculation is done and the output file is created, you will be able to view and analyse the results in the Damage Results view.

 

      1. Viewing and analysing the results of the damage stability calculations

The results of the damage stability calculations are stored in either *.ccc files (one or several real conditions) or in *.rgc files (range). The files of both types can be loaded and studied in the Damage Results view. To open the view, click Damage Results in the View menu.

 

To change the input file

  1. Press the Change button
  2. In the appeared ‘Choose the input file’ dialog box, select the file type (*.ccc or *.rgc) and the file, and press OK. The file with results of the damage stability calculations will be loaded. The results are displayed for the selected items in each of the following categories:
    • Conditions(or Draft & Trim for range)
    • Damage Cases
    • Criteria

To make a selection for the items to be included in the presentation of the result

The view has a list box for each category mentioned above. To include an item in the presentation of the result, select it in the list box. When making a selection, consider following:

  • CTRL and SHIFT buttons are used to make a multiple selection.
  • The All radio button disables the list box and all the items are considered selected.
  • The Selected radio button brings you back to the selection mode, where only the selected item are included into the presentation of the result.

To display the result

The result can be presented in several formats. To display the result, make your choice in the category lists, and press one of the following buttons:

  • Min GM, to display the table of Minimum GM values.

The table is sorted with respect to the Minimum GM value

Within each condition.

  • GM for sel. Criteria, to display a table of the Required GM values for each of the selected criteria.

The table is sorted with respect to the Minimum GM value

Within each condition.

  • Criteria, to display a Criteria Evaluation table.

The table is sorted with respect to the Required GM value within each "Condition-Damage Case" group.

  • GZ table, to display the GZ table
  • GZ curves, to display the GZ diagram
  • Limiting curves, to display and analyse the limiting curves

 

The red text colour in the table is used to highlight the rows for which the value of GM Excess is negative.

 

When the selection in the list boxes is changed, the table/diagram is greyed, as it does no longer correspond to the current selection. To update the table/diagram, press the button again.

To sort the result table

In the context menu for the active column, select Sort Ascending/Descending.

 

2.5 Design Database Tab

 

Design Database Tab is not yet implemented. For time being, use the Design Database menu to access the database elements.

 

[TO BE CONTINUED]