The easiest and cheapest way to do your structural modeling is by converting SACS input files to PREFRAME input and then push it to PREFRAME modeling. You can do it simply by running the SACS input files (usually denoted by SACINP.INP) in application called STRUMAN. This will convert your SACS input file to PREFRAME friendly file. However, new software called GENIE (from DNV, you can surf it at DNV website at ) is already smart enough to read SACS input files directly without converting it first. So, if you have old software (PREFRAME) without GENIE, you need to convert the SACS input file.

The SACS input files and model look like picture below:

After conversion using STRUMAN, you will get this PREFRAME input file:

Then, what you need to do is check your model. Here are few things that I always did during stage of modeling to ensure that I have the right conversion and model for my structure:

1-      Check the model against it drawing (see the important of data gathering?)

2-      Check the load transfer from SACS model to PREFRAME

3-      Check the properties and sections

4-      Check whether the previous modeler modeled piles within the jacket leg or not

Check out this flow chart for your modeling understanding:

After ensuring that all the model characteristics are accurate to its original, or nearly accurate in our case (really hard to make it accurateJ), we then can write T1 file. Well, T1 file is just a structural input file for WAJAC (environmental load generator) and USFOS (non-linear analysis). Think like this, T1 file bring structural genetic with it, in a form that only computer understand it so that it can perform and combine structural with environmental load to generate base shear in order for us to carry out non-linear analysis.  Here is a pick of what T1 file look alike:

You can also put a group in your model. For example if we have a huge structure with many conductors and risers in it, it is much more easier if we cluster the conductors, risers, piles, legs and bays in their own unique groups. I always did this to avoid confusions and to keep my model tidy.