With regards to the documentation of Generalized Alpha Method

[volkanozs]

Dear all,

I was wondering if the parameters in point 5 are correct or not in the documentation (gamma_M and gamma_F). I cannot understand where do they come from. In fact, I was wondering whether they are alpha_M and alpha_F or not.

https://openseespydoc.readthedocs.io/en ... Alpha.html

Thank you
Volkan

[mhscott]

Yeah, they probably should be alpmaM and alphaF. Can you verify from the paper referenced in the source code?

// Description: This file contains the implementation of the GeneralizedAlpha class.
// J.Chung, G.M.Hulbert "A Time Integration Algorithm for Structural Dynamics With
// Improved Numerical Dissipation: The Generalized-alpha Method" ASME Journal of Applied
// Mechanics, Vol 60, 371-375, 1993.

[volkanozs]

Yes, I actually already read it. Equation 19 in the paper is the same equation as the one in the documentation. beta>=1/4+1/2(alpha_f-alpha_m). I just thought that these could be some other parameters introduced in OpenSees for some reason. For example, alpha_M = 1-alpha_m (it is different that one in paper etc.), hence I wanted to ask.