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# Civil Engineering/ETABS

Question
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

Could you give me some numerical instance please?

Regards
BEH

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

Help!
QUESTION: Dear BEH,

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

Regards,
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

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

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
Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment Thank you very much for helping :)

Civil Engineering

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##### Expertise

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

##### Experience

I am experienced in the area of earthquake engineering in electrical power industry, i.e. Lifeline Earthquake Engineering. My focus has been on structural seismic design of power installations. Recently I have got involved in project management in the category of constructional engineering.

Organizations
Sinam Consulting Engineers Co.

Education/Credentials
Bs degree in Civil Engineering from Ferdowsi University ,1988, Mashhad Iran, Ms degree in Earthquake Engineering, Sharif University of Technology, 1993, Tehran, Iran