1. Identify the Loads The Building Must Support

2. It is a life-or-death matter! Under the Hammurabi Code4, written nearly 5000 years ago, if an architect designs a building that collapses and accidentally kills the owner, then the architect is to be put to death. Today architects depend on engineers to figure out how much weight a building must support, and what structures and materials are needed to support the load, plus a large safety factor.

3. 3 types of loads Dead load: The weight of the structure itself Live Load: All other forces on the object Total Load: Dead Load + Live Load

4. Examples Dead loads Floor, roof, windows, steal beam, etc. Live Load People, objects, snow, wind, water, earthquakes

5. Look at the structure of this school What is the overall shape? How many floors does it have? Is there basement? How are the floors supported? What is underneath? What’s holding up the floor you are standing on right now? Draw a sketch showing what you think is under the floor, holding it up.

6. Design challenge: Backyard Deck 1.Define the problem 2.Research the problem 3.Develop possible solutions 4.Choose the best solutions 5.Create a prototype 6.Test and Evaluate 7.Communicate the solution 8.Redesign

7. 1. Define the Problem Criteria 8 ft. x11 ft. and 3 ft high. Support at least 8 adults, 8 chairs, a table, and a charcoal grill, with a safety factor of 2 The design should be tested with a 1:12 scale model. Constraint You can only use a limited number of straws, card board strips, paper, and tapes

8. Safety factor Is the number of times greater than the maximum total load that a structure is designed to support. For example, if a structure is expected to hold a maximum total load of 1,000 ponds, a safety factor of 2 means it would be designed to hold 2,000 pounds.

9. 2. Research the problem Why research? To be original Different designs How to build a backyard deck: www.youtube.com/watch?v=WrkpZEX764k Take notes!

10. 3. Develop Possible Solutions Each of you make a rough sketch with the dimensions 8 ft. long x 11 ft. wide x 3 ft. high. Give a different name or letter.

11. 4. Choose the best solutions Remember a Pugh Chart? Create for your team to select the best design ValueDesign ADesign BDesign C Strong Support 0-5534 Low Material Costs 0-4332 Total Point 866

12. 5. Create a prototype Build your model deck with a scale of 1:12 You can only have o 8x11 cardboard o 8 straws o 2 ft. long tape.

13. 6. Test and Evaluate How many textbooks did the model hold? Did you have trouble with the deck sagging in the middle? What change can you make to strengthen it? Did you consider changing the location or orientation? If so, how did it affect the strength of the deck. Make notes on your drawing to show how you would strengthen the deck. Will this design solve the problem? If not, what design will you try next?

14. Identifying the parts Identify, joist, decking, girder, posts, and footing in your model.

15. 7. Communicate the Solution Make a scaled orthographic drawing of your final deck design. List the advantages of your design. Briefly summarize how well it performed when it was tested.

16. 8. Redesign What if you find the better way, or your client wants something a little different. You must redesign! Write a paragraph or make a sketch showing how you would redesign the deck to hold an object weighting 1,000 points in the center of the deck, with minimal cost.

17. Design Challenge: City Aquarium

18. 1. Define the Problem State the problem you have been asked to solve, and list any criteria and constraints. The problem: Criteria: Constraints:

19. 2. Research the Problem You have determined that the platform must be the same size as the bottom of the tank. You have also found that the following information: Each tank is filled until the water level is 1 foot from the top. The large tank weighs 400 lbs., and the small tank weighs 300 lbs., when empty. 1 cubic foot holds 7.5 gallons of water 1 gallon of water weighs 8.34 lbs. o How much does 1 cubic foot of water weigh? Volume =length x width x height The fish weigh 15 lbs.

20. So… Large tank 8x8x5Small tank 6x6x5 1. Weight of tank 2. Weight of fish 3. Weight of water (up to 4’) 4. Total live load (tank, fish, and water =1+2+3 5. Area of platform 6. What is the minimum pounds per square foot (psf) that the plat form must hold? =4/5 7. With a safety factor of 3, how many psf must the platform be built to hold?

21. What’s your advice? What advice would you give the director and curator? Will the platform have to be stronger to support the big tank? How much weight per square foot would the plat form need to support in each case? Were you surprised by the result?

22. Building Codes and Permits As soon as a decision has been made to build a deck or platform, it is necessary to design to meet all requirements of the local building code. A building permit must be filled out and approved by city inspectors before work can begin. How does it look like?