1. Key Question: How are buildings designed (aseismically) to withstand earthquakes?
Key Words:
Aseismic Design
Retrofitting
Land-use planning

2. Prediction seems unlikely at the moment as seismology is a relatively new science and the
earth is more complex than we once thought.
1. ‘Earthquake prediction would be useless anyway.’” Explain why
2. “Aseismic design is the best way to manage the hazard anyway? Explain why

3. Aseismic Design
List 3 things in your book that the LA City Emergency Management Operation Centre Building has to prevent EQ damage
‘Floating Building’
40 Base Isolators / Friction Pendulum Bearings
Slack in cables and pipes to don’t snap
Spare Base Isolators

4. Buildings with one of their dimensions
Building Geometry
Buildings with one of their dimensions
too large don’t perform well during EQ’ as they amplify waves. E.g. skyscrapers /
warehouses

5. Tall Building > Short Building < sway sway
Height Towers and Response to EQ’s
Tall Building >
sway
Short Building <
sway

6. ‘Pancaking’ of Buildings after Haiti EQ, 2010
Pancaking happens when insufficient steel is used and cheap concrete causes a ‘soft storey’ to collapse

9. allow the building to float and help absorb the force of shaking by
Friction Pendulum Bearings
40 base isolators
allow the building to float and help
absorb the force of shaking by
allowing the foundation to move but the building remains stationary.
LA City Emergency Management Operation Centre Building

10. Base Isolators in Istanbul Airport T4
Rubber shock absorbers can
‘dampen’ vibrations

11. Base Isolators
A ‘base isolated’ building is moved less and shaken comparably less than a fixed one during EQ’s.

12. Adding cross bracing holds the frame of the
X – Cross Bracing
Adding cross bracing holds
the frame of the
building together by increasing strength.

13. Adding X-cross bracing holds the frame of the
building together by increasing lateral strength.

14. Is another way of reinforcing a buildings frame with bracing
K – Cross Bracing (Chevron)
Is another way of reinforcing a buildings frame with bracing

15. Eccentric Cross Bracing
Adding eccentric cross bracing makes the building more ductile and twists with the EQ without failure

16. to actively sway against the building movement
Computer Controlled Counter Weights
Taipei 101 Tower, Taiwan
508 m tall sways by 60cm
Engineers installed a giant pendulum counter weight -which is computer controlled
to actively sway against the building movement

17. Trans-America Building San Francisco
Aseismic Stepped Triangular Building
Trans-America Building San Francisco
Pyramid designs are more stable for tall buildings as their wide base means upper floors shake less

18. TGC have an array of seismometers to detect EQ’s in progress
Smart Meters Tokyo Gas Company
TGC have an array of seismometers to detect EQ’s in progress
When an EQ occurs the company can cut off the gas supply remotely using a Smart Meter, preventing fires

19. Aseismically Designed Building

20. ‘Pancaking’ of Buildings after Haiti EQ, 2010
Pancaking happens when insufficient steel is used and cheap concrete causes a ‘soft storey’ to collapse

21. Retro-fitting corner Cross Bracing after Haiti ‘10
Steel and wood cross bracing can be added to the buildings that survive

22. Retrofitting
Steel shear cores increase a buildings strength

23. Full Metal Jackets
Problem! – You can’t retrofit a full City!
Steel jackets can be put around concrete supports on existing bridges to prevent them crumbling

24. Map faults and unstable geology and avoid!
Land-use planning
Seismic risk map
Map faults and unstable geology and avoid!

25. Building Regulation
Regulations can be put in place and enforced through laws. E.g. in MDC’s like USA, California you can’t build
close to faults that are proven to be active.
In LDC’s regulations are often in place but they
are not strictly policed – due to corruption / mis-
Management.

26. EQ Shake Tables
Worlds Largest Test, Japan. Colorado University

27. Modelling Buildings: Competition
Using 10 straws
Sellotape
4 pieces of A4 paper
Build a 3 storey tower over 15cm high that can take a small load.
WE WILL SHAKE TEST THEM TO FIND THE WINNERS

28. 2. As many key words about the topic in a minute
The Review Pyramid
Write down
1. 1 thing that you
now know more about
2. As many key words about the topic in a minute
3. What you want to know more about / find out next
3. This is your homework for next lesson