Steel - conc. column connection

[r2k]

I just reviewed a design in which a 54' long steel plate girder with tapering ends is used to support a lightweight roof, (14 Guage, corrugated type metal arch, span of 33' with 3' overhangs). The design for the connection to a 12x12 reinforced conc column is a simple support connection with the beam sitting on top of the column on a bearing pad with some angles anchored into the column acting as vertical and out of plain horizontal restraints. The connection allows for in-plane movement. This appears to ba a bridg-type connection which allows for some movement of the end ot the beam. Does this make sense? Would a standard bolted connection to an anchoring system into the top of the column work just as well or better? I am not familiar with the "slipping" type of connection on a building structure. Is this common?

 

[kslee1000]

Sounds like an expansion joint. Does it happen on both ends or just one? What is the mechanism to hold the roof down for uplift, by the anchored angles?

 

[csd72]

What would happen if there was an earthquake and the column toppled over?

 

[flyby911]

as a structural system this's a stable system if

1-the movement is allowed in one girder support only and not the other one too

2-concrete columns are assumed to be fixed to their foundation and not hingly supported coz their's no framing action between the girder and the columns so any lateral force (like earthquake or wind) would move the structure

3-same for out of plane .... if their's no out of plane bracing so columns have to be fixed with the foundation out of plane too

that's a reasonable solution for a 54' long girder to release one support for lateral movement coz a steel girder with that length would suffer thermal expansion whose value depends on the location of the structure,so to avoid extra stresses the designer used that solution