Cutting Existing Beam In Place
Cutting Existing Beam In Place
(OP)
I have an existing crane runway beam (W18x86) resting on a column via bolted connection through the bottom flange. The existing column has a plate welded to the top, on which the beam rests. The beam currently covers the entire plate, extending past the columns center line.
The building is having an additional built and the crane runway beam needs to be extended with it. My question is, how can I cut the beam in place, so that it is 1/4" shy of the column center line so there is a 1/2" joint between the existing beam and the new beam? I was thinking possibly plasma cutting to within 4" of the final dimension and using a bandsaw for the final cut. Would 4" be an acceptable distance to help shield the final cut section from the heat generated during plasma cutting?
Any suggestions would be much appreciated.
The building is having an additional built and the crane runway beam needs to be extended with it. My question is, how can I cut the beam in place, so that it is 1/4" shy of the column center line so there is a 1/2" joint between the existing beam and the new beam? I was thinking possibly plasma cutting to within 4" of the final dimension and using a bandsaw for the final cut. Would 4" be an acceptable distance to help shield the final cut section from the heat generated during plasma cutting?
Any suggestions would be much appreciated.





RE: Cutting Existing Beam In Place
RE: Cutting Existing Beam In Place
RE: Cutting Existing Beam In Place
RE: Cutting Existing Beam In Place
Continuous beams are only used for light cranes, and a W18X86 indicates that this is not a light crane. Shear splices are not used, as they also develop moment and result in tearing of the webs. The beam would be bolted to the cap plate, and both beams would be braced to the building column for stability.
RE: Cutting Existing Beam In Place
If the crane runway beams are simple span you could just replace the beam. I know it's a little more expensive, but it eliminates the fatigue concern. I don't see how they could cut the beam without pulling it out anyway.
You definitely do not want to use a shear splice on a crane girder. The two beams on either side of the splice would rotate opposite to each other as the crane passed over them, causing the shear plate or beam webs to tear. The new beam will need to bear on the column cap plate.