Earthquake Resistance Structures from the view point of Dynamics of Structures

1. EARTHQUAKE RESISTANCE
GROUP 2

2. STRUCTURE OF EARTH
• Earth - three layers
Crust, Mantle, Core.
• Crust - surface of Earth,
• Mantle -second inner part of the Earth,
• Core - most inner part of the Earth.

3. WHAT ARE EARTHQUAKES?
• Sudden movement - surface of the earth - may be tiny or several feet
• Enormous amounts - of energy released -greater - nuclear bomb.
• Sudden shift of rock - fracture of earth.
• Earthquakes - Plate Tectonic Forces.
• Different Boundaries - Tectonic Forces Induces Earth:
Divergent Boundary, Convergent Boundaries, Transform Boundaries.

4. • Earthquakes affect RCC structures too…
• Slabs forces the beam to bend with it when horizontal forces act.
EFFECT OF EARTHQUAKES IN RC STRUCTURES

5. EARTHQUAKE RESISTANT DESIGNS
• Design - but it is analysis of forces - buildings due to loads acting on it.
• If a building is enough to resist the earthquake, then such building is
called Earthquake resistant structure.
• Such design is called Earthquake resistant designs
 Base Isolation Devices - separate building from ground by some
rubber devices.
 Seismic dampers - special devices - introduced in building - absorb
the energy - produced by seismic waves.

6. BASE ISOLATION DEVICES
Base isolation Devices
• Energy won’t bother the structure by reducing propagation of frequency to
the structure
• Increases Flexibility
• Suitable for small to middle rise buildings
Active Control System which contains:
• Sensors - measure external excitation - structural response.
• Computer hardware and software - compute control forces – observed
excitation.
• Actuators – provide necessary control forces.

8. ENERGY DISSIPATION DEVICES
Absorbs the dynamic energy.
• Active Tuned Mass Dampers - Natural extension – Experiments
indicate 25% less damage.
• Viscous dampers
• Friction dampers
• Yielding damper

9. TUNED MASS DAMPERS

10. SEISMIC DAMPERS
• Viscous dampers- energy is absorbed
by silicone-based fluid passing
between piston cylinder arrangement
• Friction dampers- energy is absorbed
by surface with friction between them
rubbing against each other
• Yielding damper – energy is absorbed
by metallic components that yields

11. • Viscous damper

12. • Friction dampers

13. • Yielding damper

14. COMPARISON OF BASE ISOLATION DEVICES AND
SEISMIC DAMPERS
Base Isolation devices
• separating structures from ground
by means of devices.
• Can be done when structure is
already constructed, but it is
costly.
• Cheaper compared to Seismic
Dampers.
Seismic dampers
• additional systems introduced in
structures.
• even when structure is completed,
systems can be introduced.
• Very costly, since linked with
hardware programs.

15. CONCLUSION
• Earthquake is released huge energy than nuclear bomb.
• The effect is very larger than the imagination.
• So we can control the effects of the earth quacks using these type of
resistance.
• Base isolation device is more cheaper mode than seismic damper to
install to structure.

16. THANK YOU