huangyhg

fire truck loading/loads on elevated structures
i am looking for some guidance on what design loads to use on an elevated parking structure for a fire truck. we have been asked to design the structure for a ladder truck with (4) outriggers? i have no other design information. any guidance would be appreciated.
i know that i have seen engineers design for a 250psf static udl, but i do not personally think this is sufficient. i know the nbcc has a provision which is similar to this, with additional point loads required (i would think for exactly the kinds of outriggers you are talking about), however my copy of the nbcc is in canada, so i can't exactly flip to the page right now...
i would suggest that you look at a combination of bridge and building codes. no matter what the minimum requirements are, the reality is that a fire truck is not going to be pulling up nice and slow onto your slab, but screaming in and stopping pretty short.
i'll see if i can't lay my hands on a kiwi code provision and post that for you...
regards,
ys
b.eng (carleton)
working in new zealand, thinking of my snow covered home...
after looking through codes, i would contact a manufacturing company like e-one and get some actual wheel loads and outrigger loads of verious size trucks to compare to the codes.
after designing several hospital emergency canopies over the years, the one thing that i have found is that the rigs always get bigger. this has more to do with physical size than weight.
further to the nbc canada reference, part 4 is quite specific; 12 kpa (250 psf) for any structures exposed to vehicle traffic with potential exposure to loaded buses and trucks (fire trucks included) or the imposed point load of 54 kn (12 kips) for driveways and sidewalk over areaways and basements and/or areas acced by vehicles exceeding 9 000 kg gross weight.
can't comment on what our american friends require in their code.
cheers!

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