Civil Engineering Reference
In-Depth Information
Figure G7-1
Moderate-Size Roof
Step Drifts
Source: Courtesy of
Duane Becker.
the windward drift, while the rest will be transported to Roof B and thereby
be available to eventually settle at the leeward drift on Roof C. A more quan-
titative approach for roofs with two potential upwind snow sources is pre-
sented in Chapter 13.
7.1
Leeward Drift
The roof step relations are empirical, as they are based on an analysis of case
histories. For example, the leeward relation is based on an analysis of approxi-
mately 350 nominally triangular drifts recorded in insurance company fi les
Figure G7-2
Large Roof Step Drift
Source: Courtesy of
Duane Becker.
