Platforms No Leg At Center

[bobgaggle]

I'm putting a platform set together and have run into a problem. I'm using 4x8 platforms, framing is 5 1/4" by 3/4" ply. 3 toggles, 3/4" inch deck so 6" overall height. There are 6 of them bolted together, footprint is 8'x24'. They'll be legged up to 117" and I need a wide walkway underneath, so I can't drop a leg down the middle of the 8' span. I'm not comfortable only legging the 4 corners so I need a way to beef up the middle. If I do two diagonals from the center of the platform down to the corner legs, will that distribute the load to the outer legs? This is a rock show so its not like there's a chorus line dancing up there. I'm guessing 15 people on it. Thoughts?

 

[Footer]

Can you run some 2x6 or 2x8 across the US and DS edge to act as a beam and spread out that load?

 

[kicknargel]

Adding diagonal gussets as you describe will transfer some force from the middle of the span down to the legs. First, they should be bolted connections. Second, you are now adding lateral stress to the legs, causing them to want to bow out. If you're high enough to have a walkway under, you may just be transferring your problem. I'd say you either need to be 2x8 on your frame, or on your legs (with the 7.25" dimension in line with the gussets). And the bottom of the legs would need to be locked into the deck or tied together across the bottom.

 

[bobgaggle]

There we go. I can do beefier legs and will tie across the bottom. One 24' run is against a wall so I can tie into that as well. Should help the bowing. Thanks

 

[Amiers]

Are You facing the front of this or is it open?

 

[lwinters630]

I'm putting a platform set together and have run into a problem. I'm using 4x8 platforms, framing is 5 1/4" by 3/4" ply. 3 toggles, 3/4" inch deck so 6" overall height. There are 6 of them bolted together, footprint is 8'x24'. They'll be legged up to 117" and I need a wide walkway underneath, so I can't drop a leg down the middle of the 8' span. I'm not comfortable only legging the 4 corners so I need a way to beef up the middle. If I do two diagonals from the center of the platform down to the corner legs, will that distribute the load to the outer legs? This is a rock show so its not like there's a chorus line dancing up there. I'm guessing 15 people on it. Thoughts?

To span 24' you would need 2x14 on 12" centers for a live load of 60# per sf. If your thought us to throw 4x8 decks from your storage, you're adding excess weight without gaining structure.

Go look at a new home with a large span over an open basement. They are considered a dead load, yours will be very live.

If you're only spanning the 8' and running 24' long 10 ft high walls under the decks, be sure to add sway bracing both ways. 2x6 should be fine if setting on the wall.
Also check the stage to see if it will handle the point loads. I wouldn't want to read about another stage collapse.

As always don't guess, check with a pro.