IEEE TEP Activity 1 Critical Load 2010

+ IEEE TEP Activity 1: Critical Load 2010 Spring Technical English Program Санкт-Петербург, Рассия May 15, 2010 Structural engineering and How to reinforce the design of a structure to hold more weight.

IEEE TEP: Critical Load + Objectives • Communicate design objectives • Learn about efficiency ratings and critical load • Develop innovative design solutions • Work as a team and communicate in English 2

+ IEEE TEP: Critical Load Great Structures of the World Millau Viaduct • Millau, France • World’s Tallest Bridge • 2460 m long 434 m pylon height 270 m road height • December, 2004 3

+ IEEE TEP: Critical Load Great Structures of the World Yokohama Landmark Tower • Yokohama, Japan • Japan’s Tallest Office Building • 296 m tall 70 floors including office and hotel • July, 1993 4

+ IEEE TEP: Critical Load Great Structures of the World Beijing National Stadium – “Bird’s Nest” • World’s Largest Steel Structure • 258, 000 square meters • 5 years to construct • 110, 000 tons of steel used in construction • 3, 000 cubic meters • Opened June, 2008 5

+ IEEE TEP: Critical Load Great Structures of the World Crystal Cathedral • Garden Grove, California, USA • World’s Largest Glass Building • 12 stories tall 12, 000+ panes of glass • 16, 000 -pipe organ • Opened 1980 6

+ IEEE TEP: Critical Load Great Card Structures of the World Skyscraper of Cards • 2007 World Record Tallest House of Cards • Over 7. 5 meters tall • No glue or tape; just cards • Built by Bryan Berg in 2007 7

IEEE TEP: Critical Load + 8 What is Critical Load? • Force is placed on a structure • Structure can support up to a certain force, weight • • At a certain point, the structure will fail, breaking The maximum force the structure can sustain before failure is known as the “Critical Load” Force

IEEE TEP: Critical Load + Efficiency • A high critical load is not the only parameter to consider – Is the best bridge made by filling a canyon with concrete? It certainly would have a high critical load! • Consider also the weight of the structure – Lighter is better, given the same critical load • These two parameters are combined in an “Efficiency Rating”: 9

IEEE TEP: Critical Load + Your Turn • Groups of 2 • Up to 10 cards + 1 meter tape • Devise a plan to build a load bearing structure – Should have a flat top – Support load with base area of 10 x 10 cm at least 8 cm above the table • No altering of cards allowed – just tape! 10

IEEE TEP: Critical Load + 11 Your Turn Example: – Supports load – Load is at least 8 cm above table – Cards failed after load of 2. 4 kg – Structure made with 4 cards – Efficiency rating: 2. 4 kg / 4 cards = 0. 6 kg/card 8. 5 cm height

IEEE TEP: Critical Load + 12 Your Turn 1. Discuss design ideas with you partner. 2. Sketch/Draw your design on paper. 3. Predict what efficiency value you will achieve; record this number. 4. Build your design; LIMIT OF 1 METER OF TAPE! 5. Use dead weight (washers/nuts) to load your design until it fails (collapses). 6. Weigh the critical load of your structure. 7. Calculate your efficiency: [Load at Failure] / [# of cards used] 8. Discuss improvements; Answer questions on worksheet in ENGLISH!

IEEE TEP: Critical Load + Conclusion • What was your efficiency rating? How close were you to your prediction? • What made your design good or bad? • What other factors would you need to take into consideration if your Card House were a real office building? … a bridge? 13