Exploring Seismic Events: Understanding Earthquakes and Structural Engineering

1. SEISMIC OUTREACH K’NEX STRUCTURE COMPETITION University of California, San DiegoSociety of Civil and Structural Engineers

2. Introduction What is an Engineer? A person who applies scientific principles to design, construct, and understand almost all objects used by people in the world (engines, cars, bridges, machines, etc.) What do Structural Engineers do? Structural Engineers design buildings, bridges, dams, cars, helicopters, airplanes, satellites, off-shore platforms, ships and all other facilities required to sustain loads from various sources- air pressure, gravity, wind, waves, snow, impact, earthquakes, temperatures, vibrations, etc.

3. Part 1: Earthquake Phenomena Faults, Ground Motion, Measures

4. Tectonic Plates Tectonic plates - “pieces” of the earth that float on its liquid, molten core of magma. Video - how the continents moved around over Earth’s long history due to the floating of the tectonic plates.

5. Fault Types A fault is where two tectonic plates (or continents) meet. Earthquakes happen when two tectonic plates rub against each other. San Andreas Fault Pictures: http://www.ngdc.noaa.gov http://www.sms-tsunami-warning.com/pages/fault-lines#.Vg3hUPlViko http://www.iris.washington.edu/seismic/events/faults.html

6. Seismic Waves Two types of waves: 1. P waves – causes horizontal motion of the earth (compression), travels quickly 2. S waves – causes vertical motion of the earth, carries more energy, thus causing more damage Volunteer Demo! http://www.lamit.ro/sistem-avertizare-cutremur.htm

7. Ground Motion: Intensity and Magnitude • Magnitude: a measure of the amount of energy that is released from an earthquake. A magnitude of an earthquake is the same no matter where you are. • Intensity: a measure of the severity of an earthquake depending on the distance from the epicenter. Intensity changes due to the location • Difference between magnitude and intensity: some spots may “feel” an earthquake more than others not necessarily because of how far away it is from the center (or epicenter), but because of the soil it is on, what fault it is, and many other factors. (after Mavroeidis and Papageorgiou )

8. Earthquake Damage Real Cases and Reality of Problems

9. Societal Impact Dangers that an earthquake poses to a city • Power lines fall and electricity goes out. • Phone lines fall so phones don’t work. • Water and sewage pipes break, and sometimes sewage can get into water sources • Gas pipes break, causing fires (like San Francisco Earthquake). And if water pipes break, fire trucks can’t use fire hydrants. • Roads, bridges, and tunnels are ruined so emergency vehicles can’t get to people who need help.

10. Earthquake Damage Kobe Earthquake 1995 (M6.7) 5,500 deaths Video - man who is inside a skyscraper building during the Kobe Earthquake. The man is a white blob in the lower right corner. *Video on next slide

12. Earthquake Damage: Recent Cases Feb 2010 Chile (M8.8)Over 1 million homeless.700 deaths. http://www.about-knowledge.com/chile-earthquake-facts/ http://www.buzzybloggers.com/wp-content/uploads/2010/01/haiti-earthquake-2.jpg Jan 2010 Haiti Earthquake (M7.0) 92,000 deaths. 300,000 injured. 1 million homeless.http://en.wikipedia.org/wiki/2010_Haiti_earthquake http://www.nytimes.com/2010/02/28/world/americas/28chile.html

13. Earthquake Damage: Recent Cases March 2011 Japan (M8.9)Over 18,000 deaths Caused a 23-foot tsunami http://www.guardian.co.uk/world/2011/mar/21/japan-earthquake-death-toll-18000 http://www.boston.com/bigpicture/2011/03/massive_earthquake_hits_japan.html

14. Earthquake Damage: Near home! Baja California (M7.2) April 2010 – Easter Sunday Epicenter in Mexico, affected two countries Hit 300 mi radius (hit Calexico hard) Minimal damage and casualties http://abcnews.go.com/WN/earthquake-hits-baja-california-easter-sunday-damage-light/story?id=10291558

15. Structural Engineering Challenge: Solving the Problems

16. What do Structural Engineers Do? • Design the “skeleton” of the structure to increase safety by resisting forces that they are exposed to which include: • Gravity, “dead” load, “live” loads (people, furniture, cars) • Lateral Loads (forces that hit from the sides) • Wind • Earthquakes!!! Uncalculated forces from wind made the Tacoma bridge collapse (built and destroyed in 1940).

17. How Structural Engineers Plan for Disaster • Research: Mid-rise Building made from Reinforced Concrete • 7-story concrete tower that was on a real-life shake table • The building was only for testing and was destroyed after this earthquake simulation • This shake table is currently the worlds largest (in terms of area), and is actually located here in San Diego *Video on next slide

20. How Structural Engineers Plan for Disaster • Research: Two-Story Wood Frame House • Earthquake simulations on a shake table at UCSD • Houses only built for testing purposes Outside of House Inside Room of House

21. Structural Engineering Considerations for building towards safety

22. Challenge: Forces • Structures experience forces from many things: • People (Live Load) • Building’s weight (Dead Load) • Nature such as wind and earthquakes • Etc. K’NEX Education Demo!

23. Structure Components: Beams EERI, University of Notre Dame • Part of structure that span between columns and hold up the floors • Load is transferred from the floor to the beams into the columns and down to the foundation Beam Demo! Foundation

24. Structure Components: Columns EERI, University of Notre Dame Column • Part of structure that support the building (gravity loads) • Slender columns - buckling Demo! Foundation

25. Structural components: Bracing • Helps give strength to structure • Positioning helps different scenarios of “loads” and could help with money budget Arnold, C. and Reitherman, R., Building Configuration and Seismic Design, Wiley, 1982 Demo!

26. Connections Important to keep structure together in “breaks” (steel connections are better than tape) Pictures: C.M. Uang

27. Part 2: K’NEX Competition Testing your knowledge!

28. Project Scenario A rich land owner is looking for the best design of a building in downtown San Diego near an active fault. Your goal is to make a model of an appealing, original, and economical building with lots of floor space out of K’NEX. You will be placed in a Design-Build team of 4-6 to compete to win for the best design. Awards will be given to teams who do the best in certain areas.

29. The 4 Types of People Involved UCSD Students play 1. “THE OWNER” – Judge for best design; Provides money YOU in teams of students play all of the following 2. “THE ARCHITECT” – Designs the overall shape and “skin” of the building for the Owner; wants the building to be beautiful, appealing, original, and creative 3. “THE ENGINEER” – Designs the “skeleton” to hold up the “skin.” wants to strategically design the building to survive a major earthquake 4. “THE CONTRACTOR” – Builds what the Architect and Engineer have designed for the Owner; wants to build in a timely manner and on budget NOTE: Every student in a group helps play each role. One role is NOT assigned per one person. Every one helps with everything!

30. Architectural Drawing • Make the building look appealing and creative! • Colorful 3-D or multiple view 2-D Drawings • Include details such as Landscape (Plants, trees), windows, doors, building signs, balconies, people

31. Construction Drawings • Include the measurements of the width, height, and length • Provide multiple views (different floors and sides) • Be clear - Anyone should be able to build your design from your construction drawings • Use pens and rulers

32. Structural Engineering

33. Award Categories Prizes and Certificates that will be given: • Architectural Award - Best architectural rendering; most appealing and original • Construction Award - Best construction drawings; most clear and detailed with best interview • Structural Engineering Award – Best owners’ performance index of building that remains standing

34. Thank you! Questions?