ETABS MODEL Instability: How to Locate and Fix?

How to locate the joints that cause ETABS MODEL INSTABILITY? This video will show you the procedure on how to locate and fix the instability error after running a standard solver.

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[minmichmin]

Thanks a lot! This video help me solve the unstable problem suddenly.

[spyfromsparta]

I had an error while running analysis. The error was NEGATIVE EIGEN VALUES. After struggling for a bit, I searched the internet where your video suggested me to run standard solver. After running that I got the coordinates as 3, 7.5, 15. When I checked the model I found that I had replicated the vertical bracings from Grid 1 to Grid 2. As both are of different heights due to sloped roof, some joints were disconnected. After I redrew the bracings I ran the analysis again, this time without errors. So thanks for your service.

[canerozek]

i have a problem about period, may u help for the period should be around 2 sc. but it is so much low (0.1sc.)

[Paigham]

Sometimes Etabs shows huge reinforcement at station Loc 0.0 in columns what is the solution and reason of this issue?

[mehdiazizi]

I had 3 instability warnings but after set the p-delta on NONE, i got no warning.!?? how can i fix it?

[salimmwami]

Great video, very helpful. I have a problem though, apart from joints being the errors, there is also another error type named Cnstr, what is this error? if i try to locate it it takes me to a point that is within the model yes, but not part of any element of the model whatsoever, not even art of joint on model so i fail to solve it, and this error has more than 11 digits loss of accuracy. really need help on this.

[christellee]

Hello, Thank you for the video, I am getting lost of accuracy value superior to 11, but when I check the joints unique name it start with ~, for instance ~12354 and such joint doesn't exist and I don't know what wrong and how to fix it. The eigenvalues below shift = 2. Do you have any advice?

[Nataq]

I could identify the joint ant tried to solve it but, could not. Anyway, thanks for your video.

[abeedshaikh]

In model you assign fix support to all joints include all storeys joint ?why

[ajazsayyed]

Sir how to do static seismic analysis? In etab