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Jacket Generation
This is an example of the use of the macro JKT_GEN which is supplied in the tools directory. This macro generates the majority of the model for 8 pile jackets.

Most of our examples contain a common set of "beginning" commands as well as a common "ending" command. Click here to get documentation for these commands. They will not be discussed directly. The files which are discussed here are:

This macro generates a jacket model with just a handful of parameters. The macro is used in the data file, and the command file simply generates reports and plots of the model. Both of these files are discussed.

The Command File:

The command file for this sample is meant to generate summary reports and plots of the jacket generated with the macro JKT_GEN. 
$
$*********************************************      write summary
$
&SUMMARY
   GEOM
END
&STATUS FORCE
The Summary menu is entered via the command &SUMMARY. The command GEOM is an internal macro. This command generates all the reports necessary to fully document the geometric properties of the jacket model. The reports generated are:
  • class dimensions
  • material and redesign properties
  • nodal summary for part jacket
  • point summary for part jacket
  • point scf summary
  • joint property summary
  • beam properties for part jacket
  • beam section data for part jacket
  • category summary for part jacket
The next block of commands generate pictures of the jacket. 
$
$*********************************************      plots
$
&PLTMODE STRUCTURE
   PICTURE SIDE
   PICTURE TOP
   PICTURE FRONT
   PICTURE ISO
We enter the MOSES Illustrate menu with the command PLTMODE STRUCTURE command. Four pictures, a side view, a top view, a front view, and an isometric view are generated with the four command lines beginning with the command PICTURE.

That concludes the discussion of the command file. The discussion of the data file follows.

The Data File:

Before we can use the macro JKT_GEN we have to tell the program that we want to use it. This is done in the following. 
USE_MAC JKT_GEN
The command USE_MAC is an internal macro. The program will search for the specified macro starting with the current working directory and including the tools directory among others. The macro JKT_GEN is located in the tools directory along with documentation.

Before we can use the macro JKT_GEN we need to define the parameters. 

&SET WPOINT =  15
&SET TOPELE =  12
&SET WDEPTH = 275
&SET WIDTH  =  45
&SET XODIM  =  40
&SET XIDIM  =  45
&SET BATTER =  &NUMBER(REAL 1/8)
The variables set here and the parameters needed. The following table is a short description of how each variable is used.
  • WPOINT is the vertical distance between the top of the jacket and mean water level
  • TOPELE is the top elevation
  • WDEPTH is the water depth
  • WIDTH is the width of the jacket
  • XODIM is the longitudinal spacing of the outer legs
  • XIDIM is the longitudinal spacing of the inner legs
  • BATTER is the batter
Having set the parameters we immediately use the water depth variable to set the water depth in the following command. 
&PARAMETER -DEPTH %WDEPTH%
The water depth is the only parameter that needs to be set when defining a jacket. If the water depth is not set then it is possible that the resulting jacket will not sit on the sea floor.

Jacket generation begins with the PARBRA which takes as input some of the variables we defined earlier. 

PARBRA 4 %TOPELE% -%WDEPTH% %WIDTH% %BATTER% -WPOINT %WPOINT%
The macro PARBRA determines the Parallel Bracing elevations. The result of the PARBRA macro is the variable ELEV which is used in the next macros JKT_NODE and JKT_ELEM. 
&DESCRIBE BODY JACKET JACKET
JKT_NODE %ELEV% -BATTER %BATTER% -WPOINT %WPOINT% \
               -YDIM %WIDTH% -XDIM %XODIM% %XIDIM%
JKT_ELEM %ELEV% -HORIZ B D D
The command &DESCRIBE tells the program we are beginning the description of a body named JACKET. The macro JKT_NODE creates all the nodes and the macro JKT_ELEM creates all the elements needed in the jacket. The use of these two macros is discussed here.