Encampment deterrent for steel girder bridge

[tmalik3156]

Good day all.

Looking for something similar as shown in the photo below for concrete girders, except that ours is for a steel girder bridge.
We don't want to drill holes to the steel girder webs.
Does anyone have drawings / photos / ideas about how to install such a cage for steel bridges?
Thank you

 

[BridgeSmith]

Why would you want to avoid drilling holes in the webs? We do it all the time. About the only thing that's usually restricted is welding to the flanges.

 

[jhnblgr]

Make a semi integral abutment or just weld a stiffer and bolt to it

 

[tmalik3156]

Thank you for your replies.

@BridgeSmith: Near the abutment, the web is subjected to the highest shear, so we thought drilling holes into webs wouldn't be a good idea. We wanted to do something less intrusive.

@jhnblgr: Well, the bridge is already there, and it's girder-on-bearing type bridge. Near abutment, existing stiffeners are resisting high shear, so we didn't want to modify them. Adding new stiffener would require welding to the existing girder.

The kind of grating attachment shown in the photo may also have a fatigue / durability concern. The upper part moves with the thermal expansion / contraction of the girder, but the lower part is attached to the abutment which is fixed to the ground. We want avoid that as well.

Our bridge does have Chevron-bracing diaphragms between girders. May be our best option will be to hang those gratings from the diaphragms.