Bolt Shear Failure?

[Baffled Engineer]

Hello,

I'm working on an old building and I observed what appears to be a sheared bolt / damaged base plate supporting the ends of a 112' span x 8' high girder truss. See image below.

If this is related to bolt shearing, is it typical to see the white substance around the bolt? I have not seen bolts fail in shear so I can't tell if the white substance is related to this.

Thanks.

 

[bridgebuster]

Hard to tell from the photo if it's shear failure or just broken off from corrosion. what's the object at the far right - to me it looks like a transite pipe. That is probably the source of the white substance. Is this the expansion end or fixed end of the truss?

 

[STpipe]

It's hard to tell from the photo, but for the bolt on the left is that part of hole we can see?

 

[Baffled Engineer]

Hard to tell from the photo if it's shear failure or just broken off from corrosion. what's the object at the far right - to me it looks like a transite pipe. That is probably the source of the white substance. Is this the expansion end or fixed end of the truss?

The object on the far right appears to be a horizontal HSS round bracing on plan (although the load path is not clear). There is some damage on the wall of that horizontal HSS brace that looks related to the bolt damage. As for the expansion / fixed end, I don't know but they are both pinned, each end of the girder truss is bolted on top of a W-shaped column as shown below.

It's hard to tell from the photo, but for the bolt on the left is that part of hole we can see?

Yes it looks like it is part of the bolt hole...and I don't think it is a slotted connection since the other girder to column connections along this end of the building did not have a slotted hole.