EARTHQUAKE RESISTING STRUCTURE USING BALL AND PLATE

1. JAIPUR NATIONAL UNIVERSITY
EARTHQUAKE RESISTING STRUCTURES
SUBMITTED TO: SUBMITTED BY:
MR.SANJEEV SAINI MD EAKRAM AKHTAR
JNU JAIPUR DEPTT.OF CIVIL ENGINEERING
SEMESTER:VII
BATCH:2015-19

2. INTRODUCTION
 Earthquake
o Measurement of earthquake intensity
o Cause of earthquake
o Loss due to earthquake
 Earthquake Resisting Structures
 Use Of Hysteretic Dampers
 Hysteresis Loop Analysis
 Ball in cone isolation bearing
 Aim of the invention
 Background of the invention
 Object of the ball in cone isolation bearing
 Components
 parameters
 Advantages
 Load transfer
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3. OBJECTIVE
 To reduce the loss in economy.
 To improve the geological condition of the earth surface.
 Safety for lives'.
 Capability to resist more lateral and transverse moment
of the structure.
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4. EARTHQUAKE
 Earthquake is the shaking of the surface of the earth.
 It results from the sudden release in the earth’s
lithosphere that create seismic waves.
 It also cause Tsunami, landslides and occasionally
volcanic activity.
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5. MEASUREMENT OF EARTHQUAKE
 RICHTER SCALE [Outdated Method]
 SEISMOMETER
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Fig: vibration drawn by seismometer

6. CAUSE OF EARTHQUAKE
Volcanic Eruption
 The main cause of earthquake is volcanic eruption.
Tectonic Movement
 It is generally caused when rock underground suddenly
breaks along a fault.
 This movement cause seismic waves that make good
shake on the earth’s surface.
 This movement is known as rectonic movement.
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7. CONT..
 Human interference with nature.
 Geological faults.
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8. LOSS DUE TO EARTHQUAKE
 Loss of life.
 Injuries to human and animals health.
 Damages to structures.
 Ground displacement.
 Affect the local geology.
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9. EARTHQUAKE RESISTING STRUCTURE
 Earthquake resistant structures are structures designed to
protect building from earthquake.
 The goal of earthquake resistant construction is to erect
structures that fare better during seismic activity.
 Earthquake resistant structures are intended to withstand
the largest earthquake of a certain probability.
 It uses light material like wood, seismic isolation rubber
bearing.
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10. USE OF HYSTERETIC DAMPERS
 It acts as energy absorbers which limit the quasi-resonant
build up of structural deformation and forces.
 It acts as stiff members.
 It utilises solid steel beams deformed plastically in
various combination of torsional, flexural and shear
deformations.
 Different types of high capacity, low-cost hysteretic
dampers are used.
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11. HYSTERESIS LOOPANALYSIS
 It is done to analyse damage assessment through
stiffness identification using a full scale three
story steel moment resistant frame structures.
 It utilises 6 shake table tests with different
magnitudes of 3D excitations.
 The results is analysed by the difference in
stiffness over time of earthquake events.
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12. CONT..
Results
 Average difference between final and initial stiffness caused by
event are less than 5% in both horizontal and vertical direction
 It indicate good continuity and accuracy of the structure over event.
 Experimental and calculated fundamental frequency are less than
0.1 Hz.
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13. BALL-IN-CONE SEISMIC ISOLATION
BEARING
INTRODUCTION
 It consist of steel ball sandwiched between two
horizontal, steel load plates.
 The load plates have a shallow, concave, conical
recess of vertical, collinear axis
 The cone axis passes through the ball centreline at
rest.
 The load plates are bolted the structure under
and above.
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14. AIM OF THE INVENTION
 This invention relates to seismic isolation bearings for
buildings, bridges and other structures.
 Ball bearings with Non-Linear, Gravity Recentering
capacity.
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15. BACKGROUND OF THE INVENTION
 The most frequently used isolators utilize rubber for
motion decoupling and bearing recentering.
 Bearing recentering is shortly called restoring.
 Bearing's period, size and bearing capacity is limited by
the rubber's buckling and roll over state conditions
 Practical rubber bearings have
 2 second period
 50% shear strain
 1,000 psi (lb./in/in) bearing capacity
 These parameters are not suitable for near fault located
seismic isolators. 15

16. CONT..
 Rubber bearings can easily accommodate the 0.02
radian usually required bearing rotation.
 Rubber bearings are made of high damping rubber or
supplemented by dampers. That is to reduce bearing
displacement.
Friction slider bearing
 Friction slider bearings were proposed to expand these
limitations to about
 4 second period
 3500 psi bearing pressure.
 Shear strain is undefined for friction bearings
 That is the capacity of a stainless steel and Teflon lined
steel plate bearing assembly called Teflon bearing
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17. CONT..
 Teflon bearings need rubber plate bed to accommodate
bearing rotation.
 Sliding bearings have no restoring at all, thus tend to
displace one way only.
 The use of rubber plate drops bearing capacity to 1,000
psi.
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18. CONT..
FRICTION PENDULUM BEARING
 It expanded the mentioned limitations by adding gravity
restoring.
 Its friction surface is polymer-matrix coated, mounted on an
articulated slider.
 That articulation allows for bearing rotation accommodation.
 Spherical sliding surfaces provide proportional gravity
restoring.
 Friction pendulum bearings
 2 to 4 second period
 2 to 4 feet displacement
 10000 psi bearing pressure on the polymer
 average bearing pressure 1000 psi.
 The constant period is an other drawback. 18

19. CONT..
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FIG:FRICTION PENDULUM BEARING

20. MAIN OBJECT OF THE INVENTION
[BALL-IN-CONE ISOLATION BEARING]
 To provide an isolation bearing with constant
restoring and damping forces.
 Other objects are
 To provide a bearing with
 displacement independent (nonlinear) restoring
 possibility of proportional restoring steel or metal
parts only
 transitive period
 very high contact pressure
 high displacement capacity
 capacity to accommodate high bearing rotation,
 displacement limitation capability
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21. BALL IN CONE ISOLATION
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FIG 1: a ball-in-cone isolation
bearing (10)

22. COMPONENTS
Its main components are:
 load plates (11)
 a ball (12)
 holes for anchor bolting (13)
 anchor bolts (14)
 conical recess (15) in the load plate
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This represent the simplest bearing configuration, which allows for high, two-
way bearing rotations.

23. CONT..
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BEARING
COMPONENTS:
two load plates (21)
a rubber foam gasket (22)
glued to one of the two plates
four recess cones (23)
two balls (24) resting between the cone apexes (25)

24. CONT..
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multiple (four) cone bearing

25. COMPONENTS OF CONE BEARING
 The elements shown here are:
 load plate (21)
 cones (23)
 counter sink anchor bolt hole's
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26. PARAMETER OF THE BALL BEARING CONE
ISOLATION
 Contact pressure (Hertz stress) may reach the hardened
steel's yield strength (80,000-12,0000 psi).
ADVANTAGES:
 A stainless steel ball-in-cone bearing assembly need no
maintenance, inspection and replacement in service.
 Applicable materials, however are not limited to steel.
 Similarly the bearing function is not limited to seismic
isolation.
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27. LOAD TRANSFER
 The ball-in-cone bearing transfer East-West movements
to North-South movements.
 This dynamic orthogonally averages peak directional
seismic shocks in our favour.
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28. CONCLUSION
 It can resist the more amount of bearing pressure.
 The structure can move from one direction to another.
 No need of maintenance as required in the rubber
isolation
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29. REFERENCES
s.no. sources Writers/research
ers
Release date
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1 Willey digital Archives R.I.Skinner ,
J.M.Kelly,
A.J.Heine
1974
2 Bulletin of Earthquake
Engineering
J.Geoffrey
Chase,
W.rodgers,
Chikara lihoshi
17 July 2017
3 Ball in cone isolation
bearing
Zoltan A.
Kemeny, Tempe,
Ariz
4 feb ,1997

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