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Old Posted Mar 22, 2012, 5:59 AM
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scalziand scalziand is offline
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Join Date: Aug 2007
Location: Naugatuck, CT/Worcester,MA
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As the posted article notes, wood has a poor resistance to fire, which led some cities to ban wood construction for taller structures, particularly in Chicago and New York where modern skyscrapers were developed. Since wood was banned as a structural material in these main skyscraper markets, the tools and strategies for designing skyscrapers with wood were never really developed.

Strength wise, wood fares fairly well. In compression, wood is actually about as strong as concrete, while being much lighter. Wood also compares favorably to steel, since although steel is much stronger, it's also quite heavier. Wood's light weight is an advantage in earthquake prone areas.

Here's a chart of the strength to weight ratio(ksi/SG) for some varieties of wood and steel and concrete.

Data from http://workshopcompanion.com/KnowHow...d_Strength.htm

Other difficulties with designing with wood are that the strength changes with moisture content and direction of grain. For a lowrise structures, it's ok to overcome these uncertainties with deliberate overbuilding, but for a skyscraper, it's necessary to have a more consistent material.
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