How can i use eccentric loading to a column? 1

[kopernikus]

Hello

Ηow can i load eccentrically at a distance of ey in a column without missing the central charge P?
I want both loads P to exist
See the figure below

 

[Trenno]

Rigid end offsets?

[URL unfurl="true"]https://wiki.csiamerica.com/display/tp/End+offsets[/url]

 

[Agent666]

A load times an eccentricity is a moment. Apply a moment in conjunction with the axial load?

 

[kopernikus]

I don't think that's it, I think the axis should move, but how?

 

[Guest262653]

Insertion points?

 

[Trenno]

"I want both loads P to exist"

Wouldn't you then be doubling up on the axial load?

What's your action problem? Are you concerned about an unusually large eccentric beam-column connection? Perhaps provide a sketch?

 

[kopernikus]

Okay, at first the two loads are not together. Only the eccentric load P2 away from the center axle ey.
How will this load be taken into account? How to place it. It will definitely create an extra moment P2*ey.

How will the program take into account the load P2 and additional moment ?

 

[Agent666]

Apply P2 load and a moment of P2 x e_y at the same location??

 

[Blackstar123]

Yes, insertion points end length offset is the answer.
(Edit: Ops!! Sorry. I always gets confused between the two.)
Software will automatically calculate and apply the eccentric moment for the rigid length you specify through insertion points.

 

[kopernikus]

Could anyone add an example (sap2000 file)?

 

[Blackstar123]

You can easily verify it by yourself.. Simply make a 2D frame model with fixed supports. Assign end length offset to your beam. In sap you can assign end length offset by using either automatic connectivity or by providing a specific distance value from I and J ends. Run the analysis. When you check the bending moment of column, you will see there will be an additional end moment at beam-column joint which will be equal to the eccentric moment.

 

[Blackstar123]

I made a model for myself just to confirm what I've said is right. I've released beam end moments in this model just to study the intended effect of end length offset and insertion points on bending moment of columns. There's a point load of 100KN at mid point of the beam and beam ends are offset in both longitudinal and transverse direction. I've used end length offset in longitudinal direction and insertion points in transverse direction.

 

[Trenno]

Nice one, I think it's good to get in and test simple examples to check sensitivity of different things.

 

[kopernikus]

Thanks a lot for the example.
I tried it and I didn't succeed.
Would it be easy to send me the example file?

 

[kopernikus]

Where exactly did you use the options end length offset and insertion points ?

 

[Blackstar123]

My city is under lockdown for 15 days and the file is in my system in the office.

 

[kopernikus]

OK I will wait