Bearing Uplift

4 posts / 0 new
Last post
kronbk
Bearing Uplift

Does PGSuper have the ability to determine a non-zero minimum bearing reaction if there is bearing uplift at that location? In other words, can PGSuper provide a bearing uplift force for a simple span made continuous analysis?

bricer
Bearing Uplift

I'm not exactly sure what you mean. If you have a continuous 2 span bridge with the first span being very short compared to the second span, the superimposed dead load and live load will probably create uplift at the first pier/abutment. In this case, the reactions will be reported as negative values indicating that the girders at the first pier/abutment will want to lift off the bearings and a hold-down force is required.

All force effects follow a Cartesian coordinate system and right hand rule. Up is positive, down in negative.

kronbk
I have a continuous four-span

I have a continuous four-span bridge where the first spans are very long compared to the last and I would expect to see a net negative reaction as you described in your reply. However, my minimum LL reactions keep showing 0k, which seems odd to me as I would expect it to be negative. Because LL shows as zero, the minimum reaction there is equal to only the DL reaction.

No matter what span arrangements I use, the minimum LL reaction is always 0k.

bricer
Send me your input file and I

Send me your input file and I'll take a look. It could be because of the "Envelope" mode if you have enabled.

Log in or register to post comments