Globas Forces and applied horizontal forces

[Joseph]

Dear Silvia and others,

I wonder if you could tell me the relationship between the global forces (x or 1 direction) and the applied horizontal forces in the sustained push over and cyclic analyses.

To be specific with what force do I multiply the factors (steps) given as data in the drift file after a cyclic or sustained pushover analyses of a 2.5 wide wall modeled as a bar?

Background:

An in filled frame, 2.5m wide, is modeled as both a displacement and force based beam column elements with distributed plasticity and fiber section.

In the sustained push over analysis, it was observed that the global force (x or 1 direction) is twice the applied force at any given step. The deformation approximates the experimental result if half of the global force is plotted against the drift. Why is this so???

In the cyclic analysis, the applied force is equal to the applied force at any given step, yet the deformation only approximates the experimental result if half of the forces in the (x or 1) direction is plotted against the drift!!! Why?

Thank you very much, in advance, for your response and for the websites that are back after days of being down.

Joseph Olusola Idowu

[silvia]

you need to get the nodal reactions at the support to get the applied load.
the lateral load applied during a displacement-controlled analysis is only a reference load.