Load distribution in mezzanine floor
Load distribution in mezzanine floor
(OP)
Hello-
I have a mezzanine consisting of steel bar joists spanning 40', spaced at 24" o.c. with a 3 1/2" non composite concrete slab.
My client wants to install a new rack system in which the the legs of the rack fall on every 5th joist or so. My question is, if the legs fall directly over a bar joist, do you think the conc. slab is stiff enought to spread the load such that the adjacent bar joists will share the load? Or should I analyze the one joist directly below for the entire load?
Any comments will be appreciated.
thanks, Ice
I have a mezzanine consisting of steel bar joists spanning 40', spaced at 24" o.c. with a 3 1/2" non composite concrete slab.
My client wants to install a new rack system in which the the legs of the rack fall on every 5th joist or so. My question is, if the legs fall directly over a bar joist, do you think the conc. slab is stiff enought to spread the load such that the adjacent bar joists will share the load? Or should I analyze the one joist directly below for the entire load?
Any comments will be appreciated.
thanks, Ice






RE: Load distribution in mezzanine floor
This may share the bending but you will still need to design the joist under the post to take local effects all by itself.
RE: Load distribution in mezzanine floor
If I provide adequate cross bridging between the three joists under each rack leg, they will deflect the same amount and therefore evenly share the load. Does this reasoning seem correct?
RE: Load distribution in mezzanine floor
RE: Load distribution in mezzanine floor
RE: Load distribution in mezzanine floor
Rather than try to use bridging to make the joists work together, can you use a frame on top of the floor to support the legs and distribute the load to the joists? Would eliminate working from below, and also eliminate punching shear as concern if leg occurs other than on top of joist. Would still have to analyze these frame reactions to assure that load distribution to joists is acceptable.
RE: Load distribution in mezzanine floor
Ice