Product(s):	SACS
Version(s):	All.
Area:	fatigue

Problem

I am working on a Fatigue analysis using seastate input file. In the final fatigue listing file, I am facing an error: "ERROR: SEASTATE FILE ‘X’ HAS ‘N’ LOAD CASES WHERE POSTFILE ‘X’ HAS ‘M’ LOAD CASES ".

How to troubleshoot this issue?

Solution

Let us walk through this issue with an example. Say in your seainp file you have used 24 static steps for maximum base shear option as below.

And in your fatigue input file, you have called SEAS for corresponding seastate options.

In the SEAS line, you have Number of Wave Positions as 0.

You need to change this to 24, in line with seastate input wave data.

The error shall be rectified.

The SEAS line allows you to define the waves used to generate the transfer function in the seastate input file so that you don't have to define the transfer function in the fatigue input file. Sample08 is a good example of the SEAS line in action. Also, SACS Fatigue manual section 3.4.1.4 has a good explanation of the SEAS line as well as the alternative options for defining transfer functions in spectral fatigue analyses.