The following series of pages was assembled for a presentation to an 8th grade science class.  They had been studying forces, materials, simple shapes and large construction as part of a unit on building.

    I start with some historical background on types of construction and limitations of that construction.  The history of iron and steel are referenced but not investigated as that discussion would double the number of pages.  Tension forces are introduced through trusses, towers, cables and the suspension bridge.  It is hoped that students will relate some of what is discussed here to the sights they will see on an upcoming field trip.

Scott McVicker, S.E.

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