Page 224 - Forensic Structural Engineering Handbook
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7.8 CAUSES OF FAILURES
FIGURE 7.3 Drifting and sliding snow accumulation outside windows. (Credit: N. Vigener,
Simpson Gumpertz & Heger Inc.)
building can melt snow as it falls. As long as the meltwater is able to flow from the roof,
the effective weight of snow on a heated roof generally will be less than that on an
unheated surface (Fig. 7.4).
Sometimes snow and ice can be weighed accurately if measurements are made soon
after a failure, and before significant melting has occurred. A relatively simple way to
FIGURE 7.4 Roof failure of unheated skating rink, Durham, New Hampshire. (Credit:
D. Dusenberry, Simpson Gumpertz & Heger Inc.)
