|
equipment platform live load
what live load is typically used for equipment platforms? i was thinking 100 psf. ibc is not clear whether it is 60 psf or something else.
it depends on the what the platform will be used for. in the material handling industry i see 100 psf used regularly but this accounts for a lot more than just personel. this accounts for material build-up, etc. i have also seen heavier loads used when the material being processed is heavier than 100 pcf. i also think that 60 psf is reasonable if you are just looking at personel and tools, etc. in short i use some engineering judgement and see what i think the platform could see then design accordingly for 60 psf, 100 psf, etc. in general we use 100 psf quite often.
as aggman says, it depends on the the use. for industrial applications 100 psf is good since it allows for a many unexpected situations (like heavy equipment parts being placed on the platform during maintenance, or large groups of people on a plant tour).
ibc does not really give recommendations, just minimums. however if you want to "force" ibc to "suggest" a number... here is one way to look at it:
1. most platforms are accessed by stairs.
2. other than residential use, ibc 2003 says that the minimum requirement for stairs is 100 psf.
3. if the stairs are rated 100 psf, then having the platform rated 100 psf makes sense.
of course this is completely arbitrary, but if you need to "justify" a number, there is one way to do it.
you also need to check with client and see if they plan on using some sort of scissor lift or equipment on casters. sometimes these can be more trouble than the uniform load.
in the aerospace industry at launch complexes, they usually use 60 and 100 psf live load on fixed platforms depending on the location. this is done in addition to 2000 ponds concentrated load.
regards,
lutfi
thanks for the replies.
sre. that's what i was thinking as well for ibc. they have a category for "walkways and elevated platforms (other than exitways)" which has a min ll of 60 psf. ibc is not completely clear, but i think this applies to stage type platforms, not industrial. most of the platforms i've seen in power plants used 100 psf ll. i seen 150 psf on a couple occasions where buckets of powdered chemicals were stored, double stacked up on the platform. |
|