This document provides information about earthquakes and their causes. It discusses what earthquakes are, how they are caused by the movement of tectonic plates along faults, and defines key terms like epicenter. It describes the interior structure of the Earth and plate tectonics. Safety procedures during earthquakes are outlined. The types of earthquake waves and how they are measured on seismographs is explained. Finally, it discusses earthquake magnitude scales and seismic zoning in India.

1. BY : ISHAN
RAJAT
MRINAL
AVNISH
SHIFALI
BABUL
PINKEY
PIKAKSHI
PRANAV
REPORT ON
EARTHQUAKE
AND ITS DETAILS

2. CONTENTS
• Introduction
• What is an Earthquake?
• Causes
• Epicenter
• Earth’s Interior
• Plate Tectonics
• Safety Drills
• Intensity of Earthquake
• Earthquake Wave
• Indian Earthquake Zones
• Role of RCC Framed Structure

3. • Base Isolation
• How Earth is formed?
• Faults
• Plate Movement
• Design Steps for Earthquake Resistant Buildings
• Earthquake Resistant Structures
• Shape of Building
• Strengthening of Foundation and Wall
• Methods of making Flexible Design
• Earthquake Hazards

4. INTRODUCTION
• An earthquake is a series of vibrations on the earth's surface caused by the
generation of elastic (seismic) waves due to sudden rupture within the
earth during release of accumulated strain energy.
• The earth’s different layers are in constant motion, their movement is due to
many different aspects like underground volcanic activity or oceanic
movements etc.
• Due this constant motion, small intensity earthquakes occur continuously on
all faults around the world.
• Science has yet to discover a sound method of predicting these seismic
cataclysms.
• It is always beneficial to be prepared for any situation even if there are no
chances of earth quakes.

5. What is an earthquake?
• An earthquake is a shaking of the ground caused by the
sudden breaking and movement of large sections (tectonic
plates) of the earth's rocky outermost crust. The edges of the
tectonic plates are marked by faults (or fractures). Most
earthquakes occur along the fault lines when the plates slide
past each other or collide against each other.
• The shifting masses send out shock waves that may be
powerful enough to alter the surface of the Earth, thrusting up
cliffs and opening great cracks in the ground and cause great
damage ... collapse of buildings and other man-made
structures, broken power and gas lines (and the consequent
fire), landslides, snow avalanches, tsunamis (giant sea waves)
and volcanic eruptions

6. CAUSES OF EARTHQUAKE
The primary cause of an earthquake
is
faults on the crust of the earth.
“A Fault is a break or fracture b/w
two
blocks of rocks in response to
stress.”
This movement may occur rapidly, in
the form of an earthquake or may
occur slowly, in the form of creep.
Earth scientists use the angle of the
fault with respect to the surface
(known as the dip) and the direction
of slip along the fault to classify faults.

7. • Thrust (reverse)fault:
• Classification Of Faults Normal fault: a dip-slip fault
in which the block above the fault has moved
downward relative to the block below.
• Thrust (reverse)fault: a dip-slip fault in which the
upper block, above the fault plane, moves up and
over the lower block.
• Strike-slip fault: A left-lateral strike-slip fault : It is
one on which the displacement of the far block is to
the left when viewed from either side. A right-lateral
strike-slip fault: It is one on which the displacement
of the far block is to the right when viewed from
either side.

8. • Some major causes of earthquakes on basic of its
causes are:
• Surface causes Volcanic causes Tectonic causes
Surface cause: Great explosions, landslides, slips
on steep coasts, dashing of sea waves ,
avalanches , railway trains, heavy trucks, some
large engineering projects cause minor tremors.
some of them are man made, other are natural.
• Volcanic cause: Volcanic eruptions produce
earthquakes. Earthquakes may precede,
accompany and frequently follow volcanic
eruptions. They are caused by sudden
displacements of lava within or beneath the earth
crust.

9. • There are two general categories of earthquakes
that can occur at a volcano: volcano-tectonic
earthquakes long period earthquakes.
• Tectonic cause: Structural disturbances resulting in
the parts of the lithosphere is the main cause of this
type of earthquake. Most of the disastrous
earthquakes belong to this category and occur in
areas of great faults and fractures. Sudden yielding
to strain produced on the rocks of accumulating
stress causes displacements especially along old
fault zones known as great transform faults.

10. What is an Epicenter?
• The epicenter, epicentre or epicentrum is the
point on the Earth's surface that is directly
above the hypocenter or focus, the point
where an earthquake or underground
explosion originates.

11. • In the case of earthquakes, the epicenter is directly
above the point where the fault begins to rupture,
and in most cases, it is the area of greatest damage.
However, in larger events, the length of the fault
rupture is much longer, and damage can be spread
across the rupture zone.

12. Epicentral distance
• During an earthquake seismic waves propagate spherically out from the
hypocenter. Seismic shadowing occurs on the opposite side of the Earth
from the earthquake epicenter because the liquid outer core refracts the
longitudinal or compressional (P-waves) while it absorbs the transverse
or shear waves (S-waves). Outside of the seismic shadow zone both
types of wave can be detected but, due to their different velocities and
paths through the Earth, they arrive at different times. By measuring the
time difference on any seismograph as well as the distance on a travel-
time graph at which the P-wave and S-wave have the same separation,
geologists can calculate the distance to the earthquake's epicenter. This
distance is called the epicentral distance, commonly measured in °
(degrees) and denoted as Δ (delta) in seismology.
• Once epicentral distances have been calculated from at least three
seismographic measuring stations, it is a simple matter to find out where
the epicenter was located using trilateration.
• Epicentral distance is also used in calculating seismic magnitudes
developed by Richter and Gutenberg.[8][9]

13. EARTH’S INTERIOR
• Five billion years ago the Earth was formed in a massive conglomeration and
bombardment of meteorites and comets.
• The immense amount of heat energy released by the high-velocity bombardment
melted the entire planet, and it is still cooling off today.
• Denser materials like iron (Fe) from the meteorites sank into the core of the Earth,
while lighter silicates (Si), other oxygen (O) compounds, and water from comets rose
near the surface.
• The earth is divided into four main layers:
• Inner core
• Outer core
• Mantle
• Crust

14. PLATE TECTONICS
• The Earth releases its internal heat by convection, or boiling much like a pot
of pudding on the stove.
• Hot mantle rises to the surface and spreads laterally, transporting oceans
and continents as on a slow conveyor belt.
• The speed of this motion is a few centimeters per year, about as fast as
your fingernails grow.
• The new crust cools as it ages and eventually becomes dense enough to
sink back into the mantle.
• The subducted crust releases water to form volcanic island chains above,
and after a few hundred million years will be heated and recycled back to
the spreading centers.

15. • The boundary formation at the different faults is categorized according to
the type of motion of the plates at the boundary. The types are:
• Divergent Plate Boundary, in which the motion of the adjacent plates is
opposite each other.
• Mid-Ocean Ridges are created when plates collide on ocean floors.

16. • Convergent plate boundaries, in which adjacent plates collide head-on
with each other.
• In Transform plate boundaries, the adjacent plates slide against each
other.
• Complex boundaries, comprise of more than one type of movements of
the plates.

17. FORESHOCKS, MAINSHOCK
AND AFTERSHOCKS
• A major earthquake never occurs alone.
• The mainshock, which is the earthquake with the highest magnitude, is
accompanied by foreshocks and aftershocks.
• The smaller intensity shocks, which occur before the mainshock is called
the foreshock.
• The fault that moves in the mainshock experiences massive redistribution of
stress and this disrupted surface causes most of the aftershocks.
• The higher the magnitude of the mainshock, the larger the radius in which
the aftershocks will be felt. For example, the aftershock zone of magnitude 5
earthquake will be around 5 miles while that of a magnitude 8 will be more
than 200 miles.
• The quantity of aftershocks also depends on the magnitude of the
mainshock. For example, a magnitude 5 aftershock will produce in a
sequence 10 magnitude 4 aftershocks, 100 magnitude 3 aftershocks and
1000 magnitude 2 aftershocks and so on.

18. FAMILY EARTHQUAKE
DRILLS
• This will help you and your family plan and react;
remembering where to seek shelter and how to protect yourselves.
• Identify safe spots and places in each room
• Under a doorway, sturdy table, desk, or kitchen counter.
• Against an inside corner or wall; cover head with hands.
• Know and reinforce these locations by practice.
• Beware of danger zones and stay clear of
• Windows that may shatter, including mirrors and picture frames.
Heating units, fireplace, stove, and area around chimneys.
• Cabinets, refrigerators, and bookcases that may topple.
• Practice safe quake actions
Conduct drills, check reactions and choices.

19. FAMILY EARTHQUAKE DRILLS (contd.)
• Earthquake occurs with no warning; therefore, life protecting actions
must be taken at the first indication of ground shaking.
• Before the Earthquake
• Identify potential dangers in the home using common sense, fore-sight, and
your imagination to reduce risk in the event of an
• earthquake.
• Take active security measures, surveying the home for possible
• hazards.
• Take steps to correct and secure these hazards, reducing risk.
• Tall heavy furniture which could fall; fix it to a wall.
• Hot water heaters that can fall away from pipes need to be
• anchored to a wall.
• Be sure heavy mirrors or picture frames are placed away from beds and

20. • During the Earthquake
• If inside the house
• Take cover under a table or other sturdy furniture, keeping close to the floor.
Be ready to move if the cover becomes unstable or shaky.
• If there is no sturdy cover available, then stay close to a structurally sound
interior wall keeping hands on the floor for balance.
• Do not stand in doorways and move away from windows, mirrors and other
heavy objects which are unsecured.
• If in bed, cover yourself with pillows and blankets.
• Do not try to run outside and never use a lift/elevator. But if the house
construction is not sturdy then move outside cautiously.

21. • If outdoors
• Move out in the open and stay there until the shocks die off. Keep
• away from buildings, streetlights, wires and other structures.
• If the house is badly damaged, try to collect essential items,
• important documents and leave.
• Do not reenter and stay away from damaged buildings.

22. • After the Earthquake
• After the main shock, be prepared for aftershocks. They are less in intensity
but can cause further damage to structures which are weakened by the
main shock.
• Use flashlights instead of candles and lanterns to avoid fire hazards.
• If a building is safe then remain inside but if the structural damage is
questionable then evacuate cautiously.
• Provide help to trapped or injured people. Give first-aid if possible.
• Keep abreast of the latest emergency news if possible.
• Stay out of damaged buildings.
• Return home only when the authorities declare it safe.
• Check for electrical damages, gas leakages and other damages.

23. EARTHQUAKES:EARTHQUAKES:
WHY? AND HOW?WHY? AND HOW?

24. EARTHQUAKESEARTHQUAKES
• Caused by plate tectonic stresses
sudden movement or shaking of the Earthsudden movement or shaking of the Earth
• Located at plate boundaries
• Resulting in breakage of the Earth’s brittle crust

25. EARTHQUAKE DAMAGEEARTHQUAKE DAMAGE
• LandsidesLandsides
• Building damageBuilding damage
• LiquefactionLiquefaction

26. LIQUEFACTIONLIQUEFACTION
• Results in a loss of soil strength & the ability of the soil to
support weight
when a solid (sand and soil) becomes saturatedwhen a solid (sand and soil) becomes saturated
with water and actswith water and acts like a heavy liquidlike a heavy liquid

27. EARTHQUAKE INTENSITYEARTHQUAKE INTENSITY
Modified Mercalli scaleModified Mercalli scale= measurement of damage to structures= measurement of damage to structures
• From I to XIIFrom I to XII
(Roman numerals)(Roman numerals)
• Descriptive, changes withDescriptive, changes with
distance from epicenterdistance from epicenter
• Can change from locationCan change from location
toto locationlocation
What you need:What you need:
• Your senses!Your senses!
measures damage to man-made structures at certain locationmeasures damage to man-made structures at certain location

28. ISOSEISMIC MAPSISOSEISMIC MAPS
Loma Prieta EarthquakeLoma Prieta Earthquake
19891989
• Connects areas of with theConnects areas of with the
same Modified Mercallisame Modified Mercalli
numbernumber
• Areas are coloredAreas are colored
according to Modifiedaccording to Modified
Mercalli numberMercalli number
show the distribution of intensitiesshow the distribution of intensities

29. EARTHQUAKE WAVESEARTHQUAKE WAVES
• FOCUSFOCUS = place deep within the Earth and along the fault where= place deep within the Earth and along the fault where
rupture occursrupture occurs
• EPICENTEREPICENTER = geographic point= geographic point
on surface directly above focuson surface directly above focus
• SEISMIC WAVESSEISMIC WAVES produced by the release of energy
– move out in circles from the point of rupture (focus)move out in circles from the point of rupture (focus)
– 2 types: surface &2 types: surface & bodybody (travel inside & through earth’s layers)(travel inside & through earth’s layers)
• P waves: back and forth movement of rock; travel thru solid, liquid, gas
• S waves: sideways movement of rock; travel thru solids only

30. EARTHQUAKE WAVESEARTHQUAKE WAVES
SeismographsSeismographs record earthquake wavesrecord earthquake waves
SeismogramsSeismograms show:show:
• Amplitude of seismic waves (how much rockAmplitude of seismic waves (how much rock
moves or vibrates)moves or vibrates)
• Distance to the epicenterDistance to the epicenter
• Earthquake directionEarthquake direction

31. EARTHQUAKE WAVESEARTHQUAKE WAVES
• 3 types of seismic waves show up on seismogram3 types of seismic waves show up on seismogram
– P waves: shake earth in same direction as wave;
travel thru solid, liquid, gas
– S waves: Shake earth sideways to wave direction;
travel thru solids only
– Surface waves: circular movement of rock;
travel on surface – cause most damage!!

32. EARTHQUAKE WAVESEARTHQUAKE WAVES
Body P waves S waves
waves
AKA
Moves
through
Movement
of rock
Primary (1st to arrive)
Longitudinal, Compression
all states of matter
(solid, liquid, gas)
back and forth movement of rock
• push/pull or compression/stretch out
• Like slinky down stairs
Vibration is same as the direction of
travel
Secondary (2nd to arrive - larger)
Transverse, Shear
Can go through solids only
Move sideways
• perpendicular to direction of wave
travel
• Like snake

33. EARTHQUAKE WAVESEARTHQUAKE WAVES
Lets test your understanding!!
Is this a P or an S wave?
P wave!
S Wave

34. EARTHQUAKE WAVESEARTHQUAKE WAVES
P waves move through solids & liquids
S waves move through solids only!!!

35. EARTHQUAKEEARTHQUAKE MAGNITUDEMAGNITUDE
measures the size of seismic wavesmeasures the size of seismic waves 
the energy released by the earthquakethe energy released by the earthquake
Richter scaleRichter scale=measurement of energy released=measurement of energy released
based upon wave amplitude (size of vibration)based upon wave amplitude (size of vibration)
• <2 to ~10<2 to ~10
• Amplitude of wave goes upAmplitude of wave goes up
by 10 (Logarithmic scale)by 10 (Logarithmic scale)
What you need:What you need:
• Amplitude (size of vibration = wave height)Amplitude (size of vibration = wave height)
• Time between arrival of 1Time between arrival of 1stst
P and 1P and 1stst
S wavesS waves

36. MERCALLI VS. RICHTERMERCALLI VS. RICHTER

37. INDIAN SEISMIC ZONE
&
SOME DANGEROUS EARTHQUAKE

38. ZONING IN INDIA
• ZONE 1
• ZONE 2
• ZONE 3
• ZONE 4
• ZONE 5

39. EARTHQUAKES IN INDIA
The major earthquakes in India are
2004 Sumatra Earthquake (9.1)
1934 Bihar Earthquake (8.7)
1950 Assam (Shillong Plateau) Earthquake (8.7)
1897 Assam (Tibetian Plateau) Earthquake (8.5)
2005 Kashmir Earthquake (7.6)
2001 Gujarat(Kutch) Earthquake (7.1)

40. EARTHQUAKE ZONES IN INDIA
There are five seismic zones named as I to V based on Modified Mercalli
Scale (MM Scale) as details given below:
Zone V: Covers the areas liable to seismic intensity IX and above on MM
Scale. This is the most severe seismic zone and is referred here as Very
High Damage Risk Zone.
Zone IV: Gives the area liable to MM VIII. This, zone is second in severity to
zone V. This is referred here as High Damage Risk Zone.
Zone III: The associated intensity is MM VII. This is termed here as
Moderate Damage Risk Zone.
Zone II: The probable intensity is MM VI. This zone is referred to as Low
Damage Risk Zone.
Zone I: Here the maximum intensity is estimated as MM V or less. This zone
is termed here as Very Low Damage Risk Zone.

43. EARTHQUAKE ZONES IN INDIA
Zone V: Kashmir, Punjab, the western and Central Himalayas, the North-
East Indian region and the Rann of Kutch fall in this zone.
Zone IV: Indo-Gangetic basin and the capital of the country(Delhi, Jammu)
and Bihar fall in Zone 4.
Zone III: The Andaman and Nicobar Islands, parts of Kashmir, Western
Himalayas, Western Ghats fall under this zone
Zone II: Other parts of India namely Hyderabad, Lakshadweep, Orissa etc.
Zone I : No

44. EARTHQUAKE ZONES IN INDIA
Cities and Zones
• Zone III :- Ahemdabad, Vadodara, Rajkot, Bhavnagar, Surat,Mumbai, Agra,
Bhiwandi, Nashik, Kanpur Pune, Bhubneshwar, Cuttack, Asansol, Kochi,
Kolkata, Varanasi, Bareilly, Lucknow, Indore, Jabalpur, Vijaywada, Dhanwad,
Chennai, Coimbatore, Manglore, Kozhikode ,Trivandrum.
• Zone IV :- Dehradun, New Delhi, Jamunanagar, Patna, Meerut, Jammu,
Amristar,Jalandhar.
• Zone V:- Guwahati and Srinagar.

45. ROLE OF R.C.C
FRAME
STRUCTURE ON
EARTHQUAKE
RESISTANCE
STRUCTUCE

46. BASIC DESIGN PRINCIPLES
• PLANNING AND LAYOUT OF THE BUILDING
• GENERAL LAYOUT OF THE STRUCTURAL FRAMING
• CONSIDERATION OF HIGHLY LOADED AND CRITICAL
SECTIONS WITH PROVISION OF REINFORCEMENT AS
REQUIRED
• STRUCTURE SHOULD NOT BE BRITTLE
• RESISTING ELEMENT MUST BE PROVIDED
• ALL ELEMENTS SHOULD BE TIED TOGETHER
• THE BUILDING MUST BE WELL CONNECTED TO GOOD
FOUNDATION AND EARTH
• GOOD QUALITY MATERIAL SHOULD BE USED
THROUGHOUT THE CONSTRUCTION

47. Click to add text
Plan of building
-Symmetry
-Regularity
-Simplicity
-Separation of Blocks
-Enclosed area
-Separate Buildings
for Different
Functions
Choice of site
GENERAL PLANNING AND
DESIGN ASPECTS

48. TECHNIQUES TO RESIST EARTHQUAKE
• Shear walls
• Bracing
• Dampers
• Rollers
• Isolation
• Light weight material
• Bands
• Others

49. SHEAR WALLS
Resist;
• Gravity Loads
• Lateral Loads

50. ACTIVE AND PASSIVE SYSTEM
ACTIVE SYSTEM
• THIS SYSTEM PROVIDES SEISMIC PROTECTION BY IMPOSING
FORCES ON A STRUCTURE THAT COUNTER BALANCE THE
EARTHQUAKE INDUCED FORCES
PASSIVE SYSTEM
• PASSIVE SEISMIC CONTROLS ARE PASSIVE IN THAT THEY
DPO NOT REQUIRE ANY ADDITIONAL ENERGY SOURCE TO
OPERATE AND ARE ACTIVATED BY EARTHQUAKE INPUT
MOTION ONLY

51. BRACING
Diagonal Cross Chevron
Eccentric
Link
Beams

52. DAMPERS

53. LIQUID TUNED MASS DAMPER
One Rincon Hill, San Francisco

54. ROLLERS

55. ISOLATION

56. BASE ISOLATION MECHANISM

57. BANDS

58. WASTE TIRE PADS

59. MATERIALS AND BASIC UNDERSTANDING
• Shape (configuration) of building:
– Square or rectangular usually perform better
than L, T, U, H, +, O, or a combination of
these.
• Construction material: steel, concrete, wood,
brick.
– Concrete is the most widely used construction
material in the world.
– Ductile materials perform better than brittle
ones. Ductile materials include steel and
aluminum. Brittle materials include brick,
stone and unstrengthened concrete.

60. BASE ISOLATION
 Base isolation is a passive vibration control system.
 The goal of base isolation is to reduce the energy that is transferred from the
ground motion to the structure.
(a) Conventional structure (b) base isolated structure.

61. THE PURPOSE OF BASE ISOLATION
 As for all the load cases encountered in the design process, such as gravity and
wind, should work to meet a single basic equation:
CAPACITY > DEMAND.
This can be achieved by,
 Ductility
EFFECTS OF DUCTILITY
 Leads to higher floor accelerations.
 Damage to structural components, which may not be repairable.

62. TYPES OF ISOLATOR
 Lead rubber bearing (LRB)
 Flat sliding bearing (PTFE)
COMPONENTS OF LRB

63. Effects of Base Isolation System

64. Application of Base-isolated
Structure
• １） Government and Municipal Office,
• Fire Station, Police Station,
• Broadcasting Station
• ２） Hospital, Social welfare facilities
• ３） Laboratory
• ４） Computer Center
• ５） Museum, Gallery, Library
• ６） Apartment House
• ７） Cultural Asset, Historic Structure

66. 4.6 Billion Years Ago4.6 Billion Years Ago
 With the rise of the sun, the remaining
material began to clump up. Small
particles drew together, bound by the force
of gravity, into larger particles. The solar
wind swept away lighter elements, such as
hydrogen and helium, from the closer
regions, leaving only heavy, rocky
materials to create smaller terrestrial
worlds like Earth. But farther away, the
solar winds had less impact on lighter
elements, allowing them to coalesce
into gas giants. In this way, asteroids
,comets, planets, and moons were
created.

67. ..
 Earth's rocky core formed first, with heavy elements colliding
and binding together. Dense material sank to the center, while
the
lighter pieces created the crust. The planet's magnetic field
probably
formed around this time. Gravity captured some of the lighter
elements that make up the planet's early atmosphere.
 Early in its evolution,
Earth suffered an impact
by a large body that catapulted
pieces of the young planet's
mantle into space. Gravity
caused many of these
pieces to draw together and form
the moon, which took up orbit
around its creator.

68. ..
 Although the population of
comets and asteroids
passing through the inner
solar system is sparse
today, they were more
abundant when the planets
and sun were young.
Collisions from these icy
bodies likely deposited
much of the Earth's water
on its surface. Because the
planet is in the Goldilocks
zone, the region where
liquid water neither freezes
nor evaporates bur can
remain as a liquid, the
water remained at the
surface, which many feel
plays a key role in the
development of life.

69. ..
400 Million Years Ago
 Life begins developing in the form of trees
and plants. These produce more oxygen.
Earth has a cooler temperature, with
changeable weather. This weather (rain,
snow, wind, frost) causes the tops of the
ancient volcanoes to wear away, creating
lower ground. Dinosaurs eventually develop,
ruling the planet. Flowers are later formed,
along with insects.
65 Million Years Ago
 Life was wiped off the face of the planet! It
is believed that a huge meteorite or comet
hit the Earth's surface, causing clouds of
dust which suffocated the dinosaurs and
other creatures on the planet. Conditions on
the planet were suffocating as poisonous
chemicals were unable to leave the planet's
atmosphere, and life-giving energy from the
Sun could not enter. After settling again, the
Earth was suitable for life, an the ancestors
of human beings developed.

70. TodayToday
 Earth is still developing.
Volcanoes still erupt, the
earth still shakes, weather
still forms landscapes.
Creatures evolve. Some go
extinct, others adapt to
the changing planet.
Nobody knows what the
future holds. The air is
becoming more polluted,
and the temperature on
the planet is gradually
rising. Earth remains a
target for meteors, comets
and asteroids travelling
through space.

71. Naturally occurring earthquakesNaturally occurring earthquakes

72. Different types of FaultsDifferent types of Faults
A close look at faults
helps geologists to
understand how the
tectonic plates have
moved relative to one
another.
Types of movement of
crustal blocks that can
occur along faults
during an earthquake:

73. The Awatere FaultThe Awatere Fault
cuts a clear linecuts a clear line
across the hills. Itacross the hills. It
last ruptured in thelast ruptured in the
1848 Marlborough1848 Marlborough
EarthquakeEarthquake

74. Plate TectonicsPlate Tectonics
 The Earth’s crust is
divided into 12 major
plates which are
moved in various
directions.
 This plate motion
causes them to collide,
pull apart, or scrape
against each other.
 Each type of
interaction causes a
characteristic set of
Earth structures or
“tectonic” features.
 The word, tectonic,
refers to the
deformation of the
crust as a
consequence of plate
interaction.

75. Plate MovementPlate Movement
“Plates” of
lithosphere
are moved
around by
the
underlying
hot mantle
convection
cells.

76. Divergent
Convergent
Transform
Three types of plate boundary

77. Spreading ridges
◦ As plates move apart
new material is
erupted to fill the gap
Divergent
Boundaries
Convergent
Boundaries
There are three styles of
convergent plate boundaries
--Continent-continent collision
--Continent-oceanic crust
collision
--Ocean-ocean collision

78. Continent-Continent-
ContinentContinent
CollisionCollision
Forms mountains, e.g.
European Alps, Himalayas
Ocean-Ocean
Plate Collision
When two oceanic plates collide, one
runs over the other which causes it to
sink into the mantle forming a
subduction zone.
The subducting plate is bent
downward to form a very deep
depression in the ocean floor called a
trench.
The worlds deepest parts of the ocean
are found along trenches.
E.g. The Mariana Trench is 11 km
deep!

79. Where plates slide past each other
Transform Boundaries
Above: View of the San Andreas
transform fault

81. Where do earthquakes form?Where do earthquakes form?
Figure showing the tectonic setting of earthquakes

82. Plate Tectonics SummaryPlate Tectonics Summary
The Earth is made up of 3 main layers
(core, mantle, crust)
On the surface of the Earth are tectonic
plates that slowly move around the
globe
Plates are made of crust and upper
mantle (lithosphere)
There are 3 types of plate boundaries
Volcanoes and Earthquakes are closely
linked to the margins of the tectonic
plates.

83. Liquefaction :
Liquefaction is a phenomenon in which the strength and stiffness of a soil is
reduced by earthquake shaking or other rapid loading. Liquefaction and related
phenomena have been responsible for tremendous amounts of damage in
historical earthquakes around the world.

85. Landslide:
A landslide, also known as
a landslip, is a geological
phenomenon that includes a wide
range of ground movements, such
as rockfalls, deep failure ofslopes
and shallow debris flows

86. DESIGN STEPS FORDESIGN STEPS FOR
EARTHQUAKE RESISTANTEARTHQUAKE RESISTANT
BUILDINGS.BUILDINGS.

87. GEOMETRYGEOMETRY::
 Building need to be proportioned reasonably to avoid
unduly long, tall or wide dimensions which are
known to result in poor seismic performance during
an earthquake. Thus urban by-laws tend to control
the overall geometry of the buildings with respect to
the plot size. These are helpful in controlling
problems like blockade of roads or collapsing on
adjacent buildings in an unfortunate situation of a
building collapse during an earthquake.
 Height/plot width <1.3 as per clause 6.6 NBC(1983)
(part III) for plot size and clause 9.4.1 for height.
Ex: plot area 10.0x18.0m-Max.permissible height=
1.3x10=13.0m
 Length to width ratio<1.66 Clause 6.6 NBC & 8.2.1
for side open space.
 Ex: helps in ensuring rigid diaphragm action.

88.  Plot area 12mx20m
-deduct standard setbacks.
-Remaining maximum coverage area:6.0mx15.5m.
-Maximum possible plan size: 6mx9.6m.
LENGTH OF BUILDING:
 Shall not be more than 150m.
 Clear height of 6m at every 30m intervals at ground
level for a passage of 7.5m width.
30m
150m (max)
6m
7.5m

89.  Thermal consideration requires expansion joints after
every 45m. These joints become seismic joints in
buildings locates in seismic zones. In such situations,
the 150m specified is not relevant.
OTHER CONSIDERATIONS:
IS 1893 Provisions.
-Improve shape and subsequently
behavior of
building during earthquake shaking.
Design provisions may not exist to
explicitly limit the height of buildings. But, it
is desirable to ensure that
- Buildings are not made too long.
- Building height gives a regular (desired)
slenderness ratio.

90. 6. For cantilevers it is designed for gravity and other loads as
usual for the top bars and thickness but designed in addition to
that as per the is code 1893-2002 clause 7.12.2.2 which
states: All horizontal projections like corniced and balconies
shall be designed and checked for stability for five times the
design coefficient specified in 6.4.5(that is =10/3 Ah).
HOW TO INCREASE THE DUCTILITY :
Ductility; is defined as the ability of a structure to undergo inelastic
deformations beyond the initial yield deformation with no
decrease in the load.
RESISTANCE CAN BE INCREASED IN A SECTION BY:
1. Decrease the percentage of tension steel (pt).
2. Increase the percentage compression steel (pc).
3. Decrease in the tensile strength of steel. (Fy=415N/mm^2).
4. Increase in the compressive strength of concrete.-Min M20 to
M30 and above.
5. Increase in the compression flange area in flanged beams (T
and L beams) and
6. Increase in the transverse (Shear) reinforcement.

91. Earthquake-resistant StructuresEarthquake-resistant Structures

92. While it is not possible to accurately predict earthquakes, measures can beWhile it is not possible to accurately predict earthquakes, measures can be
taken to reduce the devastation by constructing earthquake-resistanttaken to reduce the devastation by constructing earthquake-resistant
structures. Earthquakes have the ability to level entire office buildingsstructures. Earthquakes have the ability to level entire office buildings
and homes, destroy bridges and overpasses, roads, and breakand homes, destroy bridges and overpasses, roads, and break
underground water lines. In some cases, building practices are not up tounderground water lines. In some cases, building practices are not up to
code, and in the event of an earthquake, the loss of life is catastrophic.code, and in the event of an earthquake, the loss of life is catastrophic.
In earthquake-prone areas, buildings are now being constructed withIn earthquake-prone areas, buildings are now being constructed with
moorings filled with alternating layers of rubber and steel. These aremoorings filled with alternating layers of rubber and steel. These are
called base isolators. The rubber acts as an “earthquake absorber.”called base isolators. The rubber acts as an “earthquake absorber.”
Buildings with these types of moorings are designed to withstand aBuildings with these types of moorings are designed to withstand a
magnitude 8.3 earthquake.magnitude 8.3 earthquake.
In attempts to reduce damage to structures, engineers try toIn attempts to reduce damage to structures, engineers try to
Increase the natural period of the structure through “base isolation.”Increase the natural period of the structure through “base isolation.”
Install “energy dissipating devices” to dampen the system.Install “energy dissipating devices” to dampen the system.

93. Simple reinforcement methods used by engineers include usingSimple reinforcement methods used by engineers include using
large bolts to secure buildings to their foundations, as well aslarge bolts to secure buildings to their foundations, as well as
providing supporting walls, or shear walls, made of reinforcedproviding supporting walls, or shear walls, made of reinforced
concrete. This can help to reduce the rocking effect of a buildingconcrete. This can help to reduce the rocking effect of a building
during and after a seismic event.during and after a seismic event.
Shear walls at the center of the building (around an elevator shaft)Shear walls at the center of the building (around an elevator shaft)
can form a shear core.can form a shear core.
Employing cross-braces, where walls are built with diagonal steelEmploying cross-braces, where walls are built with diagonal steel
beams, adds extra support.beams, adds extra support.
World Book illustration by Dan Swanson, Van
Garde Imagery

94. SHAPES OF BUILDINGSHAPES OF BUILDING

95. The behaviour of a building during earthquakes depends critically on its overall shape,The behaviour of a building during earthquakes depends critically on its overall shape,
size and geometry, in addition to how the earthquake forces are carried to the ground.size and geometry, in addition to how the earthquake forces are carried to the ground.
Sometimes the shape of the building catches the eye of the visitor, sometimes theSometimes the shape of the building catches the eye of the visitor, sometimes the
structural system appeals, and in other occasions both shape and structural systemstructural system appeals, and in other occasions both shape and structural system
work together to make the structure a marvel.work together to make the structure a marvel.
Size of Buildings:Size of Buildings: In tall buildings with large height-to-base size ratio (Figure 1a),In tall buildings with large height-to-base size ratio (Figure 1a),
the horizontal movement of the floors during ground shaking is large. In short but very longthe horizontal movement of the floors during ground shaking is large. In short but very long
buildings (Figure 1b), the damaging effects during earthquake shaking are many. And, in buildingsbuildings (Figure 1b), the damaging effects during earthquake shaking are many. And, in buildings
with large plan area like warehouses (Figure 1c), the horizontal seismic forceswith large plan area like warehouses (Figure 1c), the horizontal seismic forces
can be excessive to be carried by columns and walls.can be excessive to be carried by columns and walls.

96. Horizontal Layout of Buildings: In
general,buildings with simple geometry
in plan (Figure 2a) have performed well
during strong earthquakes. Buildings
with re-entrant corners, like those U, V,
H and + shaped in plan (Figure 2b),
have sustained significant damage.
Many times, the bad effects of these
interior corners in the plan of buildings
are avoided by making the buildings in
two parts. For example, an L-shaped
plan can be broken up into two
rectangular plan shapes using a
separation joint at the
junction (Figure 2c). Often, the plan is
simple, but the columns/walls are not
equally distributed in plan. Buildings
with such features tend to twist during
earthquake shaking. When irregular
features are included in buildings, a
considerably higher level of engineering
effort is required in the structural design
and yet the building may not be as good
as one with simple architectural
features.

97. STENGTHENING OF FOUNDATION AND WALLS
Strengthening of structural system are very necessary because if
foundation isnt strong enough to with stand the load, the whole
building will collapse.
• If the soil is loose, we choose pile foundation for the building till
the pile reach the hard strata of earth at that region. If the hard
strata isnt reachable, the pile is made with some friction
component so that it creats a frition with soil so that it binds with
the loose soil.
• Dampers are also used to soak the vibration occure due to
earthquake. Rough
surface for
creating
friction with
the soil

98. • Strengthning of wall:
1. Walls can be strengthened by making a good bonding in the brick
work.
2. Framed structure is advisable so that walls are just used as in
filling. So that loads are transffered by beam and columns , wall
should not bear any load
3. Shear can be used to make structure stable .
4. Diagonal braces can also be used to make walls more strong.

99. METHODS FOR MAKING FLEXIBLE DESIGN
Flexible design for making earthquake resistant building is to make
building in a grid form and as well as framed structure.
Framed structure is advisable so that all the all load are directed
towards the foundation of the building.so that infilling of walls can
be made flexible as per the requirement.

100. EARTHQUAKE HAZARD
• Ground Shaking: Shakes structures constructed on ground causing
them to collapse.
• Liquefaction: Conversion of formally stable cohesion-less soils to a
fluid mass, causing damage to the structures.
• Landslides: Triggered by the vibrations
• Retaining structure failure: Damage of anchored wall, sheet pile,
other retaining walls and sea walls.
• Fire: Indirect result of earthquakes triggered by broken gas and
power lines.
• Tsunamis: large waves created by the instantaneous displacement
of the sea floor during submarine faulting

101. THANK YOU