Snow depth calculation in metric in ASCE 7-05
Snow depth calculation in metric in ASCE 7-05
(OP)
In ASCE 7-05 Section 7.7.1, at the bottom, it says to determine the snow depth (h.b) by dividing the snow load (p.s) by the snow density (gamma). This is all fine and good, makes perfect sense. But then in parentheses there is this note: "In SI: also multiply by 102 to get the depth in m.)
This doesn't make any sense to me, as determining depth by dividing pressure by density is not an empirical formula, and shouldn't need any "coefficients" to correct for different units systems. If I'm in SI, I have density in N/m^3, and I have load/pressure in N/m^2, so pressure/density should give me the depth in meters without multiplying by any special number. What am I missing here? (I thought that maybe the note is assuming that you are going to try to divide psf by N/m^3, but I did the math to see what the conversion factor would be in that situation and it's not 102.)
This doesn't make any sense to me, as determining depth by dividing pressure by density is not an empirical formula, and shouldn't need any "coefficients" to correct for different units systems. If I'm in SI, I have density in N/m^3, and I have load/pressure in N/m^2, so pressure/density should give me the depth in meters without multiplying by any special number. What am I missing here? (I thought that maybe the note is assuming that you are going to try to divide psf by N/m^3, but I did the math to see what the conversion factor would be in that situation and it's not 102.)






RE: Snow depth calculation in metric in ASCE 7-05
RE: Snow depth calculation in metric in ASCE 7-05
They usually dont just remove mistakes from books or codes...they note them and reference some sort of errata.
RE: Snow depth calculation in metric in ASCE 7-05
Also, I found a link on the SEI website to a form called "Proposal to Revise the 2005 Edition of ASCE 7": htt
RE: Snow depth calculation in metric in ASCE 7-05
I kid.
RE: Snow depth calculation in metric in ASCE 7-05
If you were only working with flat roofs, you'd never calculate "ps".
RE: Snow depth calculation in metric in ASCE 7-05
RE: Snow depth calculation in metric in ASCE 7-05
I'll consider adding the thing about pf/ps, it is really strange that they removed pf from the 05.
RE: Snow depth calculation in metric in ASCE 7-05
RE: Snow depth calculation in metric in ASCE 7-05
RE: Snow depth calculation in metric in ASCE 7-05