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-   -   snow accumulation around elevated mechanical uni (http://www.dimcax.com/hust/showthread.php?t=28973)

huangyhg 2009-09-15 11:53 PM

snow accumulation around elevated mechanical uni
 
snow accumulation around elevated mechanical unit
hi all,
when calculating snow accumulation, do you consider a mechanical roof unit elevated by 1.2m stub-columns same as if it is not elevated ?
thanks to your input
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i would normally consider it having a height of 1.2m plus the height of the mechanical unit. in addition, in canada, there is a manner of calculating a snow accumulation around a roof top unit.
dik
the ibc allows snow buildup to be neglected if the rooftop unit is less than 15' long on each side.
daveatkins
the nbc of canada isn't quite so generous... dik
dik:
i understand snow accumulates when wind blows the snow and when snowflakes hit a barrier; they fall and accumulate beside that barrier. in this case the wind can blow under the unit and disperse the accumulated wind. therefore, i think there should be some reduction in the accumulation.
it's not so much the snow hitting the barrier, but the change in wind velocity around obstructions that tends to cause snow to 'precipitate' when the localized velocity is diminished.
dik


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