Snow load calculation according to CTE DB SE-AE (3.5.1 and Annex E - Spanish code).

• The CTE Code proposes a way of get the snow load from the height, the climatic area and other parameters. This calculation only covers "the cases of snow normal drop. In roofs accesible for people or vehicles, the possible acumulations due to artificial snow movements must be considered. Also the particular constuctive conditions that permits snow accumulations must be considered".
  
  
• The snow load calculation with this program has to be made for each roof slope.
  
  
• The load on snow slide bareers elements can be obtained from the snow mass that can slide. It can be supposed that the sliding factor between the snow and the roof is null (CTE DB SE-AE 3.5.1, ap.5).
  
  
• This program does not cover the calculation of the snow load due to discharge over elements under the roof, with slopes over 30º, showed at CTE DB SE-AE 3.5.4.
  
  

Parameters:
Location:	By province capitals
Province capital:	.AlbaceteAlicanteAlmeríaÁvilaBadajozBarcelonaBilbaoBurgosCáceresCádizCastellónCiudad RealCórdobaCoruñaCuencaGeronaGranadaGuadalajaraHuelvaHuescaJaénLeónLéridaLogroñoLugoMadridMáflagaMurciaOrenseOviedoPalenciaPalma de MallorcaPalmas, LasPamplonaPontevedraSalamancaSan SebastiánSantanderSegoviaSevillaSoriaTarragonaTenerifeTeruelToledoValenciaValladolidVitoriaZamoraZaragozaCeuta y Melilla.
Height =	660	m
Climatic zone =	4
Building with storeys	Yes
Wind exposition:	.ShelteredRegularExposed.	(*1)
Sliding roughness	Yes
Slope angle =		o
Down limited with cornices or limateses	Yes
(*1)The reduction of the snow load on sheltered buildings is an option. Select "Regular" in those cases for considering no reductions.
		Unlimited calculations for users with an active subscription. (+info)

Results:
Snow load over horizontal land Sk =	0.6	kN/m2		CTE DB SE-AE 3.5.2, table 3.8
Shape factor μ =	0.67			CTE DB SE-AE 3.5.3, ap.2
Exposition factor Fex =	1			CTE DB SE-AE 3.5.1, ap.3
Snow load qn =	0.4	kN/m2 (*3)		CTE DB SE-AE 3.5.1, ap.2
Snow load in real proyection qnv=	0.31	kN/m2 (*4)			qnv = qncos(40)
(*3)Hoizontal proyeced load. Useful at horizontal roofs and with programs where the load has to be defined in an horizontal plan and is proyected over the sloped wedges.
(*4)Real size load. Useful with programs (like Tricalc) where the load the load is defined right at the sloped plans.

• The code says "In horizontal roofs of buildings with storeys located at places lower than 1000 m, considering a snow load of 1 kN/m2 is enough", without verifying the wind exposition. It gives conservative values because there is only one city (León) with a snow load higher than 1 kN/m2.
  
  
• As can be expected, is not allways accurate the correspondance between the snow load showed at table 3.8 of province capitals with those showed at the annex fron the height and the climatic zone. This is due to at table 3.8 only one decimal is used, and sometimes it is not rounded to the closer but to the higher value (case of Cáceres, Ciudad Real, Cuenca and Pamplona). This is why one decimal has been used for Sk when selecting province capitals, and two decimals when calculating with height and climatic zone.
  
  

Version 01/08/2012