operable soundproof partition support

[ajk1]

I am checking an existing steel beam floor support to see if it can also support a new soundproof operable partition hung from it (the beam is actually a pair of side-by side steel beams and the door can be suspened so that the load is shared by them). Since these are floor beams, when the live load is on the floor (it is a banquet hall/auditorium floor), the beams will deflect -- about 3/8" under Code live load of 100 psf, although the actual live load on the floor possibly could be taken as signifcantly less than 100 psf for deflection calculation for this purpose. I am doubtful that there will be much allowance for deflection within the door assembly (I will try to check with the manufacturer on Tuesday), because if there were, it would probably adversely affect the degree of soundproofing. If this were new constrcution, I would design a beam to support the hung operable partition, that was independent of the floor. Has anyone encountered this situation of suspending a soundproof operable partition from existing steel floor beams and if so, how have you dealt with it? (The beams are adequate for strength to support the new operable partition that weighs 22 psf).

 

[hokie66]

The door should be able to accommodate that much deflection. Just tell the manufacturer how much the support will deflect from live load above and from movement of the door, and let him design the door to suit.

 

[shobroco]

I've hung an operable soundproof partition from an existing steel roof beam to divide an existing conference room & deflection turned out to be a big problem. The beam was about L/360 deflection with the added load, irrelevant to an SAT ceiling, so I did some minor reinforcing after talking to the partition suppliers, who said that if plaster won't crack they are okay. Everything was fine through the summer but the following winter snowloads made the bi-parting partition drag on the floor track, and the centre stile would not latch. L/1200 deflection was too much for a 3m high 12m long door. The manufacturers assume absolute rigidity in their designs.

 

[ajk1]

Thank you Shobroco. What you describe as happening is precisely what my supervisor told me would happen when I started as a young engineer 48 years ago, and he said that was why our company always suspended operable partitions from steel beams that were independent of the roof.

I will nevertheless give a call to the partition manufacturer of Tuesday to get their input, but if he tells me that deflection is not a problem, I shall be very skeptical!

I wonder if there are operable partitions that can be supported from the floor slab, as in my case the floor slab is a slab-on-grade.

 

[ajk1]

But if he tells me that they can design for the defelction, then I suppose I can accept that.

 

[concretemasonry]

ajk1 -

Make sure your position is in writing and you have their acceptance in writing. Don't rely on a phone, but you already know that after 48 years and I also of the same vintage. Somehow verbal acceptances for the convenience of progress are not always remembered

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[ajk1]

concretemasonry: Precisely.