1. Structural Stresses 8 th Grade Industrial Technology

2. Structural Stresses Objective  To identify the four structural stresses as they act on structures Compression Tension Torsion Shearing

3. Structural Stresses Structural Stresses Table of Contents  Compression Compression  Tension Tension  Torsion Torsion  Shearing Shearing Click to Select a Specific Stress

4. Structural Stresses Compression Definition  Forces that cause material to be pushed together  Causes materials to buckle Back to Table of Contents

5. Structural Stresses Compression Example Click here then select squeezing force

6. Structural Stresses Tension Definition  Forces that cause material to be pulled apart  Tension causes materials to snap Back to Table of Contents

7. Structural Stresses Tension Example  Cables are under tension stress Tension Click here then select stretching force

8. Structural Stresses Torsion Definition  A force that causes materials to twist and bend Back to Table of Contents

9. Structural Stresses Torsion Stress in Action Tacoma Narrows Bridge in high wind before it collapsed (click below for video) Click here then select twisting force

10. Structural Stresses Shear Definition  A stress that causes materials to tear or slide by each other Back to Table of Contents

11. Structural Stresses Shear Example  Shear stress causes materials to tear apart Click here then select sliding force

12. Structural Stresses Review Table StressPictureDescription TensionPulling CompressionPushing TorsionTwisting ShearingSliding

13. Structural Stresses Structural Stresses Question  Which type of stress would you apply to your pencil if you wanted it to break it? Why would you choose this stress?

14. Structural Stresses Structural Stresses Answer  Shear stress  Shear stress would be the easiest stress you could apply to break your pencil  A pencil would require larger amounts of compression, tension, or torsion than could be applied by hand.

15. Structural Stresses Resource  Brusic, S., Fales, J., & Kuetemyer, V. (2004). Technology today and tommorow. New York: Glencoe.