Seismosoft | Earthquake Engineering Solutions

Hello,

I selected 100 as the number of modes i wanted in a eigenvalue analysis but it giver a "Unknow error" and it only gives me 38 modes. Why did this happen and why cant i get the 100 modes?

It only gives me 82% and 91% in cumulative masses for x and y.

Thank you in advance,
Lucas.

If you using the Lanczos algorithm, try the more stable Jacobi with Ritz transformation algorithm. Note that if you have a basement the basement masses are extremely difficult to get activated, due to the lateral supports.
Seismosoft Support

I dont have basement floors and I am using the Jacobi with Ritz transformation algorithm. What more can I do?