Weston Middle School
Technology/Engineering Course Materials
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Demo: Compressive Strength of a Paper Cup
Start with 8 paper cups- test-remove 1 -retest- remove 1- repeat----
80 pound student is supported by 4 paper cups
3 paper cups---failure!
Compressive strength of cup = 80/4= 20 lbs
Demo: Compressive Strength of An Egg
Measuring compressive strength of teacher
Science Wing Foundation Walls -Concrete Mixed with Rebar
Soil Testing Apparatus to Measure Compressive Strength of Subsoil
Skeletal Bones consist of a matrix of collagen fibers, a protein which is stong in tension (collagen is the main component of skin and tendons), similar to rebar.This matrix is then filled in with calcium salts, which are strong in compression, analogous to concrete.
Thus bone, like the highway columns, is strong in both tension and compression.
Demo: Saw open turkey bones.
Social Studies Connection: Roman Concrete
Failure in tension and compression- Laval Overpass Collapse, Montreal, October 2006
Revised January 2011 by Jonathan Dietz, firstname.lastname@example.org