Civil Engineering/ETABS

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QUESTION: Good Day Sir,
I'm new in ETABS, probably would need sir to help me.

a) I was increasing the stiffness of building (shear wall, increase column size, and put bracing) to resist seismic. But from "Story Response Plot", it show that the maximum displacement keep increasing. Suppose to decrease right?

b) Was wondering what does the Story Response Plot means in ETABS? Does it means the MAXIMUM LIMITS for each particular floor? or it means the ACTUAL deformation?   

Thanks

ANSWER: Dear JV

Could you give me some numerical instance please?

Regards
BEH

---------- FOLLOW-UP ----------

Help!
Help!  
QUESTION: Dear BEH,

Thank you for replying my msg. The attachment below shows my explanation to my previous questions. Thanks.

Regards,
JV

ANSWER: Dear JV

Are you using modal method?

regards
BEH

---------- FOLLOW-UP ----------

QUESTION: Dear BEH,

Nope. I am using:

Display Type = Max Story Displacement
Case/Combo = EQX
Output Type = Max
Load Type = Load Case

Remark: The "EQX" is from earthquake time history and it is nonlinear analysis.
Between, should I use Modal Analysis? What is the difference between Load Cases and Modal cases? sorry, i was confused. Thanks.

Regards
JV

Answer
Dear JV

Got it! When you use time history analysis you are using the energy content of earthquake in higher period for non braced system. When you brace it you use higher energy content related to lower periods . Then you have greater displacements . But the matter is that you must use a series of accelerogram and calculate the average of the responses of all earthquakes . This is well done when you use modal- spectral method or somply quasi static method.

Regards
BEH

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Babak Esmailzadeh Hakimi

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I can answer questions in Structural Engineering, Earthquake Engineering, Project Management and Project Control topics!

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