1. Materials & Joints Designing Structures

2. Things to consider when designing a structure... 1. Function 2. Aesthetics (how it looks) 3. Safety 4. Cost Efficiency 5. Materials

3. Materials

4. 3 Types of Materials Composite Layered Woven or Knit

5. Composite Materials Made from two or more kinds of material 2 types of forces act on a composite material tension compression Ex: bricks, concrete

6. Layered Materials Layers of different materials are pressed and glued together Combines properties of different materials Layers are called laminations Ex: windshield, drywall, winter jacket

8. Woven or Knit Materials Spinning, twisting, looping, or knotting fibers together gives materials strength Ex: steel cables, rope

9. Choosing Materials Weigh the advantages vs. disadvantages of various materials Factors to consider: Costs (is cheaper always better?) Appearance Environmental Impact Energy Efficiency

10. Joints

11. 2 Types Mobile Rigid

12. Mobile Joints Joints that allow movement

13. Rigid Joints Rigid joints do not allow movement Several Types Fasteners Inter-locking Shapes Ties Glue Melting

14. Fasteners Rigid joints do not allow movement Lack of movement can be a strength OR a weakness (depending on function) Holes made in structure actually weaken structure Ex: nails, bolts, screws, rivets

15. Inter-locking Shapes Fits together because of shape Ex: lego, dovetail joint, dental fillings

16. Ties Fasten things together Ex: thread, string, rope

17. Adhesives Sticky substances hold things together Ex: hot glue, drying glue, epoxy resin

18. Melting Pieces of metal or plastic can be melted together Ex: welding, soldering, brazing

19. Choosing Joints Weigh the advantages vs. disadvantages of various joints Factors to consider: Function Costs