2. FORCES STRUCTURES DESCRIBING STRUCTURES STRESS, FATIGUE, FAILURE Grab Bag 10 20 30 40 50

3. FORCES - 10 The __________________ is an external force that all structures have. This force occurs due to the WEIGHT of the structure on itself.

4. FORCES - 10 DEAD LOAD

5. FORCES -20 What is Tension? Is it an Internal or External? Can you give a real life example?

6. FORCES -20 Tension is the Internal Force that causes stretching, pulling, or tightening within a material. Life Examples: Tug-Of-War (rope tension) Cables of a suspension bridge

7. FORCES -30 What force crushes a material by squeezing it together?

8. FORCES - 30 Compression

9. FORCES – 50 The external force of the wind, rain, snow and the weight of things that are in or on a structure (People/Furniture) are called …

10. FORCES – 50 Live Load

11. FORCES – 40 Draw Force Vectors (arrows) to label at least 4 different forces acting on a skyscraper *Must include BOTH Internal and External Force

12. FORCES – 40 Wind, Rain, Snow, Hail, Sleet External: Weight of people and things inside Weight of the structure on itself (External) Which causes Internal Compression of the materials Gravity

13. Structures - 10 A structure that does not occur naturally in the environment and that is created by people is called a __________________________ structure.

14. Structures - 10 Manufactured

15. Structures - 20 Can be made by… piling up or forming similar materials into a particular shape or design

16. Structures - 20 Solid Structure (also known as a Mass Structure)

17. Structures - 30 Structures that keep their shape and support loads without a frame or solid mass material inside, are called _______________. These structures use a thin, carefully shaped, outer layer of material, to provide their strength and rigidity.

18. Structures - 30 Shell Structures

19. Structures - 40 WHAT IS A STRUCTURE --- FILL IN THE BLANKS Structures have definite __________and _____________, which serve a definite purpose or ___________________. Every part of the structure must resist ______________(stress such as pushes or pulls)

20. Structures - 40 Structures have definite SIZE and SHAPE, which serve a definite purpose or FUNCTION. Every part of the structure must resist FORCES (stress such as pushes or pulls)

21. Structures - 50 Besides Aesthetics… what are some of the major considerations designers/architects must consider when building a structure. Hint * Think of some of the discussion topics you needed to cover in your Ice Hotel Commentaries OR Think of some of the things you needed to consider in your Design Structure Projects

22. Structures - 50 Function (What is the Purpose of the Structure) Form (Solid, Shell, Frame… which will work best) Materials (What would be the best materials to choose) – pro’s and con’s Cost (What is the cost of all of the above going to be… what is the budget?) Safety (Is the design safe, can it support its own dead load… … how much of a live load can it support?)

23. Describing Structures -10 The shape, texture, color, type of material, symmetry and simplicity of the repeated pattern used in the design of structures is?

24. Describing Structures -10 AESTHETICS “LOOKS”

25. Describing Structures - 20 The following words describe the _______ of a structure? · containing (substances) · transporting · sheltering · lifting · fastening · breaking · holding

26. Describing Structures - 20 FUNCTION

27. Describing Structures - 30 What is another name for a frame structure that uses triangles for strength and support?

28. Describing Structures - 30 TRUSS

29. Describing Structures - 40 The combination of compression and tension occurring at the same time results in what force?

30. Describing Structures - 40 BENDING

31. Describing Structures - 50 What are the 4 principles of stability?

32. Describing Structures - 50 Principles of Stability 1) Build a firm foundation 2) Balance Forces 3) Keep the thrust line vertical (Centre of Gravity) 4) Use Rapid Rotation

33. Stress, Fatigue, Failure - 10 True or False Structures are in STRESS only when extremely large forces begin to damage, break, or crack the structure.

34. Stress, Fatigue, Failure - 10 False Structures are in stress as soon as ANY external and internal force act on the structure causing some change (such as a small amount of internal force).

35. Stress, Fatigue, Failure - 20 TRUE OR FALSE ??? The Leaning Tower of Pisa was under a great amount of stress due to the soft ground, compression, sinking of the building, cracking of the building, and forces such as gravity working against it.

36. Stress, Fatigue, Failure - 20 TRUE!

37. Stress, Fatigue, Failure - 30 Watch the Following Video… When is the structure stressed? Fatigued? Does it Fail? https://www.youtube.com/watch?v=lXyG68_caV4

38. Stress, Fatigue, Failure - 30 Stress: External Forces cause some Internal Change Fatigue: Torsion and Shear Forces begin cracking and damaging components of the bridge Failure: Bridge Collapses

39. Stress, Fatigue, Failure - 40 To reduce stress and internal force within the ground we can increase the surface area of a structure against the ground. Give an example of how this can be done or a life example of a structure that is designed to increase surface area to spread the force of a load.

40. Stress, Fatigue, Failure - 40 Snowshoes Snowboards A Large Foundation (Concrete Slab) 2 Feet on the ground rather than one or tip toes

41. Stress, Fatigue, Failure - 50 What is lamination and how does lamination help reduce possible fatigue of a structure?

42. Stress, Fatigue, Failure - 50 Lamination is a method of strengthening a material. By bonding two materials together, you are creating a stronger structure. Ex: Bonding plastic to paper (laminating a poser for example) will help reduce fatigue, damage… such as rips or tears.

43. GRAB BAG - 10 What unit of measurement is used to describe the magnitude (size) of a FORCE?

44. GRAB BAG – 10 Newtons (N)

45. GRAB BAG - 20 The ___________________ is a wobbly, unstable shape. When you push the side (apply force) it flops into a slanted parallelogram. This happens without any of the rectangle’s sides changing length.

46. GRAB BAG – 20 RECTANGLE / SQUARE

47. GRAB BAG - 30 Describe Corrugation What is a corrugated material?

48. GRAB BAG – 30 Corrugation is the addition of arches or ridges within a material to allow the material to better resist the internal force of compression. * Arches spread the force evenly throughout and strengthen the material

49. GRAB BAG - 40

50. GRAB BAG – 40 Dead Load: Weight of the Train on itself and on the tracks Live Load: Weight of the load Put in to the train cars Gravity Thrust of the train forward Friction acting against the train on the tracks Normal Force of the ground back up External Forces: Wind, Rain, Sleet Compression within the tracks

51. GRAB BAG - 50 Choose one of the following Sports or Activities and as a team draw a FORCE DIAGRAM on the board. The Diagram must include at least 3 External Forces, 1 Internal Force You must also choose 2 Structures needed for the sport and label their structural form (Solid, Shell, Frame, or Combination) Snowboarding, Volleyball, Tennis Quidditch, Jumping on a Pogo-Stick, Rock Climbing

52. GRAB BAG – 50 Snowboarding, Volleyball, Tennis Quidditch, Jumping on a Pogo-Stick, Rock Climbing