Earthquake resistance structures

Earthquake Resistance Structures

Presented byD.Uday Kumar and

J.Prasad

Sudden movement of earth surface is called Earthquakes

The structures able to resist earthquake induced vibration is known as earthquake resistant structures

Such design is called Earthquake resistant designs

INTRODUCTION

NATURAL ACTIVITIES Due to movement of

tectonic plates Due to faults present

beneath the earthHUMAN ACTIVITIES Construction of dams Ground water extraction Skyscrapers Fracking and Injection wells

WHY DO EARTHQUAKES HAPPEN?

Shaking Ground moves in the same place Land slides Ground is moved to some another place Liquifaction Strength of the ground is reduced causing buildings to sink

HOW EARTHQUAKES AFFECT BUILDINGS?

Ground acceleration and building damage

The damage that a building suffers primarily depend not on displacement but on acceleration

Building stiffness Taller buildings are more flexible

than shorter buildings Ductility Ductility is the ability to undergo

deformation Damping Moves forward and backward

HOW BUILDINGS RESPONED TO EARTHQUAKES?

BASE ISOLATION DEVICES

Base isolated structure is supported by a series of bearing pads which are placed between building and building foundation

Lead rubber bearing is sandwiched between two steel plates

HOW DO YOU MADE AN EARTHQUAKE PROOF BUILDING?

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building is supported by bearing pads that have a curved surface and low friction

building is free to slide on the bearings

SPERICAL SLIDING ISOLATION SYSTEMS

Reduce the building acceleration by ¼ the acceleration of fixed base building

Acceleration decreased because the base isolation system lengthens the building's period of vibration.

Rubber is highly elastic so reduce the damage

Converts the kinetic energy as heat

RESPONCE OF BASE ISOLATION BUILDING

Also called energy dissipation devices

Which absorb vibrations caused due to earthquakes

TYPES Viscous dampers Reduce the vibrations by fluid action Tuned mass dampers Reduce the vibrations by harmonic

action

DAMPERS

COMPONENTS Piston Rod Cylinder Fluid Seal Piston Head Seal Retainer Accumulator

VISCOUS DAMPERS

Also known as a harmonic absorber

Mounted in structures to reduce the amplitude of mechanical vibrations by harmonic motions

Prevent discomfort and damage

It is a Lightweight component COMPONENTS Spring Oscillating Mass Viscodamper

TUNED MASS DAMPERS

We are only hope of tomorrow’s constructions.

‘’ WE ARE HERE ONLY TO PROVIDE SAFETY TO PUBLIC TO LEAD THEIR LIFE ‘’

HAPPILY

CONCLUSION

www.multyscience.co.ukwww.institute of structuralengineer.comwww.faddoengineers.comTechnological advance in Japanese building design and constructionhttp://www.taipei-101.com.tw/en/Tower/buildind_13-1.htmlhttp://www.esm-gmbh.de/EN/Products/Tuned_mass_dampers

REFERENCES:

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