GK12 Review Presentation C.J. DeGroot St. Louis Charter School
Three Units Designing and Building File-Folder Bridges Build a Model Truss Bridge Test the Strength of Structural Members Analyze and Evaluate a Truss Hazard Mitigation Letter Tsunami Brochure
Designing and Building File-Folder Bridges Brief introduction to engineering What is engineering? What do engineers do? What type of people are engineers? What different types of engineering exist? What things do engineers work on? Types of Engineering
Designing and Building File-Folder Bridges Learning Objectives: Build a Model Truss Bridge Identify different types of bridges Explain what a truss is Identify the major components of a truss bridge Identify types of truss bridges Explain fundamental engineering concepts: Force, Load, Reaction, Equilibrium, Tension, Compression, Strength Explain how a truss carries load Explain the roles of owner, design professional, constructor, project manager Explain how construction quality affects structural performance
TeachEngineering.org Activity Tension or Compression? Write down if the items indicated in the following pictures are in tension or compression
Tension or Compression? 1. Chain of a swing
Tension or Compression? 2. Leg of a swing set
Tension or Compression? 3. Leg of a desk
Tension or Compression? 4. Bike Chain
Tension or Compression? 5. Spoke
Tension or Compression? 6. Arm http://www.healthstylesexercise.com/catalog/images/Perfect-Pushup.jpg
Tension or Compression? 7. Arm http://z.about.com/d/weighttraining/1/0/Z/0/-/-/pullup1.jpg
Tension or Compression? 8. Tennis Ball http://people.rit.edu/andpph/photofile-c/tennis-ball-rebound-2a.jpg
Tension or Compression? 9. Racket Strings http://people.rit.edu/andpph/photofile-c/tennis-ball-rebound-2a.jpg
Tension or Compression? 10. Shoelace http://www.acasports.co.uk/images/products/full/adidas_adipure_sg.jpg
Tension or Compression? 11. Clothes in a full suitcase http://farm2.static.flickr.com/1399/989922244_9c0ed3bf6e.jpg?v=0
Tension or Compression? 12. Kite string http://rick.files.wordpress.com/2008/06/kite_fight.jpg
Tension or Compression? 13. Power lines http://www.liquidmatrix.org/blog/wp-content/uploads/2007/08/powerline.JPG
Tension or Compression? 14. Tripod legs http://www.liquidmatrix.org/blog/wp-content/uploads/2007/08/powerline.JPG
Tension or Compression? 15. Spring http://www.ux1.eiu.edu/~cfadd/1350/08PotEng/Images/8.2.gif
Tension or Compression? 16. Truss member DK
Designing and Building File-Folder Bridges Learning Objectives: Test the Strength of Structural Members Calculate cross-sectional area of a member Describe yielding, rupture, and buckling failure Explain the factors that affect the tensile strength and compressive strength of a member Design a testing program to determine the strength of structural members Explain the principle of the lever and apply it Determine the tensile strength and compressive strength of structural members experimentally Use a computer to analyze and graph data
Principle of the Lever Forces must be balanced Moment must be balanced around the fulcrum
Tensile Strength Graph
Compressive Strength Graph
Designing and Building File-Folder Bridges Learning Objectives: Analyze and Evaluate a Truss Calculate the components of a force vector Add force vectors Explain fundamental engineering concepts: Free body diagram, equilibrium, structural model, symmetry, static determinacy, stability, factor of safety Use the Method of Joints to calculate the internal force in truss members Determine the strength of every member Evaluate a truss to determine if it can safely carry a given load
Add Force Vectors
Add Force Vectors
Add Force Vectors
Method of Joints
Hazard Mitigation Letter Learned about structural and nonstructural earthquake mitigation (focused on nonstructural) Learned Mitigation Techniques for: Computer Equipment - Gas shut-off valves Hot water heaters - Windows Pictures and Mirrors - Flexible gas lines Bookcases/cabinets - Chimneys/Masonry Light Fixtures - Securing heavy objects Library stacks - Signs/Bulletin boards Securing heavy equipment
Hazard Mitigation Letter Learned what to do before, during, and after an earthquake Broke into two groups for “inspecting” the school Each student was responsible to write a persuasive letter about how the school could be made safer through earthquake mitigation techniques
Tsunami Brochure For the globalization requirement, we studied the 2004 Indian Ocean Tsunami Students chose a particular country to focus on Students were responsible for their own research Amy and I provided guidance (no Wikipedia, etc.) Students each made a three-panel informational brochure with Microsoft Publisher Information about tsunamis Information about their country Information about rebuilding in their country