Bearing Pad Check

[ATHS]

Contractor made an error in placing the girder. Girder web is not concentric with bearing pad after girder erection. Center of girder web is at an offset of approx 1.5" from the center of bearing. What calcs does one show to justify this shouldn't be a problem ?

 

[MIKE_311]

Is the bearing pad offset or the girder? Isn't there an end diaphragm there? wouldn't that inhibit the placement of a diaphragm or the cross frames near girder end?

I would have them jack and reset it or THEY should demonstrate it's ok to leave as is. You shouldn't have to justify a contractor error unless the owner is asking you to verify.

 

[bridgebuster]

Sounds like a project I have under construction. The girder is in the right place but the bearing is off. The bearing manufacturer submitted calculations showing the bearing will work; although the owner may have a different opinion.

 

[ATHS]

@Bridgebuster, what kind of calculation was it ? Do you have any info ?
@Mike 311, the bearing is at an offset.

 

[BridgeSmith]

The only effect I can see is a small torsional moment on the girder due to the eccentricity between the bearing load and the center of the supporting force. Assuming the flange is adequately supported by the bearing stiffeners, and the cross frames/diaphragms can resist that moment, I don't see an issue, unless the shift in the bearing load applied to the seat causes an overstress in the cap.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[bridgebuster]

@ATHS - on my project we have multi-rotational disc bearings with sole and masonry plates. The manufacturer checked all of the components. The only thing that was affected by the eccentricity was the thickness of the sole plate. However, the thickness provided still exceeds what is required.