prestress/jacking force 1

[bluefish74]

I have a tiechord(steel plate built-up section) in my bridge which take about 2000kips jacking force before the bridge deck in place. How can I model this force in sap2000?

 

[IJR]

That is a tough issue bluefish

But try to assign a P-delta force to your tiechord frame element. It is the simplest method and it allows you to run an elastic analysis.

P-delta force is not associated with any load case. It is there in the member throughout. So use it with care because it will be there even when you assign other loads.

If it works fine, that will be great. Else, you will have to do nasty nonlinear analysis

respects
ijr

 

[bluefish74]

thanks for the tip, what if I use the command assign>frame load> strain, and use strain=force/Area of tiechord. Does that do the same job?

 

[IJR]

That(the strain loading) is very tempting bluefish.

I tried it a couple of times and I didnt like the result. there is something there that I apparently miss.

But try it, if it works then you are rolling

respects
ijr