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# Civil Engineering/Etabs 13 Load Pattern

Question
QUESTION: Dear sir,

First I would like to thank you for your efforts.

My question is :
In Etabs 13 they gave you the ability to define earthquake (static) into one single load pattern. If you go to see forces resulting from a combination including that pattern (BMD for example) you will find three options : Max, min & absolute max.

I wonder which one the design is carried out with?
Also, the absolute max gave me the max negative value but it didn't do so with the max positive one.

Note : I did my test on a column with EQ Static and defined Comb1=1.0EQ to compare the results of each step in the case with the combination.

Best regards.
Wael AlOqaily

If you display the design results on the frame, then right click on the member you wish to check on, the tables will display which governing load case or combo the design is based on.

[an error occurred while processing this directive]---------- FOLLOW-UP ----------

QUESTION: Thanks for answering my question. But it seems that I need to make some explanation to get you to the point.

Suppose that the controlling combination Ucon3=1.2D+1.0EQ

Since EQ involves 6 steps (X,Y,X+e,Y+e,X-e & Y-e),
how can I know which step is used in calculation of combination Ucon3 ?

Hi Wael,

OK, I understand now. What you will need to do is look at the governing design forces when you right click on the member displaying the rebar and make a note of these. Then you go to Display>Tables>Column/Beam Design forces and scroll down to where the EQXY forces are listed.  These will have 1 to 6 as suffixes against the EQXY load case, so you can then compare the values.

I believe that is the only way to check. Of course you could define the X and Y cases separately, to make such interrogation easier.
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