no eigen vectors? 1

[Baltali]

I have warnings in my analysis log and modal analysis can not be performed.

-I tried removing all files except .edb
-I changed mass sources of the building in order to examine any change
-There is a sub-story between 2 stories. I have created it by using "move" command. It is something like +6.75 btw +4.5 and +9.00. Is it possible that ETABS can not see it as a mass source and breaks?
-I wish i could attach the docs but company does not allow.

Thank you.



Warnings:


* * * W A R N I N G * * *
SUBSPACE VECTORS ARE NOT INDEPENDENT,
MODEL OF STRUCTURE MAY BE NUMERICALLY SENSITIVE,
RE-RUN ANALYSIS WITH A DIFFERENT FREQUENCY SHIFT


NUMBER OF EIGEN MODES FOUND = 0
NUMBER OF ITERATIONS PERFORMED = 1

 

[jenofstructures]

if there's problem in eigenvector try the RITZ Vector it will run with more iteration than the eigen vector

in your mass source there are three type of loadings

1. from self and specified massnly self weight will be a part of the base shear
2. from loads:from here you can compute the base shear, based on what will you prefer (like you can choose the dead plus the SDL plus the load or you can just prefer the SDL plus the live load)
3. From self and specified mass and loads:you can enter your additional load (because the base shear will automatically add the self weight)

 

[Baltali]

jenofstructures thank you for your response but my actual problem is not "how to add mass sources to your structures"

Additionally, Ritz Vector is not working properly too.

 

[jenofstructures]

are you trying to say that there's a mezzanine between those floors?

try to model it as a story too and not use the reference line on it