Structural Proportion: Induction and Deduction
    Review points from lecture 25
    Arch 324/624, Introduction to Structural Design, University of Virginia
     Copyright © 1996-2006 Kirk Martini. Last Modified Mon, 23-Apr-2007 10:00
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    • Trends in structural proportion can be developed by induction or deduction.

      • Induction means deriving general principles by observing many specific examples.

      • Deduction means applying general principles to predict the outcome of a specific case.

    • Both induction and deduction lead to the following conclusions:

      • The span-to-depth ratio for beams ranges from about 10:1 to 40:1.

      • About 20:1 is a normal looking beam. Beams may become more slender when lightly loaded, and less slender when heavily loaded.

      • Beams become more slender with increasing span, up to the point where self weight begins to dominate. This is typically at spans at 200 feet or beyond.

    Arch 324/624, Introduction to Structural Design, University of Virginia
     Copyright © 1996-2005 Kirk Martini. Last Modified Mon, 23-Apr-2007 10:00    		   Table of
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