Steel Floor Plate

[lewisec9]

We are covering an open pit with steel framing and steel raised pattern floor plate. I have been searching for a specification for the connection of the plate to the steel.

Is a continuous fillet weld acceptable or do we need a skip weld to accomodate expansion? Do we need a gap for expansion between plate?

I would appreciate your input! Thank you

 

[jike]

You definitely need a small gap all around for proper fitup. This would vary depending on how large an opening. Unless it is a huge opening with large temperature variation, expansion is most likely not a problem for a small fill-in.

Options for fastening: stitch welding, self tapping screws or proprietary mechanical fasteners. If environment requires continuous welding, then add seal welds between stitch welds.

 

[Bagman2524]

Table 3-18 in the AISC manual is a good reference for raised pattern floor plate.

"Look for 3 things in a person intelligence, energy and integrity. If they don't have the last one, don't even bother with the first 2. W. Buffet

 

[racookpe1978]

Such steel plate is (usually!) removable for cleaning, access, equipment repair and replacement and removal from the pit, maintenance, etc. Separate plates will always have small gaps due to fitup and bolting.

Also, floor plates are (usually) shipped around 4x8 feet and are installed separately and bolted down separately. Unless the whole assembly is one continuous (welded) piece many, many feet larger than that 4x8, thermal expansion under "typical" climate conditions will not be a large problem.

Remember, the plate is expanding from heating or cooling, but so are the support beams and the girders. The concrete foundations not as much (ground temps are less variable) but a covered large pit not exposed to direct sunlight will be around 65-70 at the bottom even in summer.