active isolation

7/27/2019 Active Isolation

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OUTLINE

1. INTRODUCTION

2. LITRATURE REVIEW

3. SEGMENTAL BUILDING & BASE-ISOLATEDSTIFFENED SUPERSTRUCTURE BUILDING

4. PROGRAM FOR MDOF SYSTEM

5. PROGRAM VERIFICATION

6. WORK TO BE DONE IN NEXT PHASE

7. REFERENCES


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Active Mass Damping Active Bracing

Active Tendons

Base-Isolation Energy Dissipation

Tuned Mass Damper

Stiffness Control Devices Electro/Magneto

Rheological Damper Friction Control Devices

Detailing of Reinforcement as perIS-13920 Provisions

3

1 INTRODUCTION

Earthquake Resistance

Methods

Ductile DetailingMethod

Response ControlMethods

Active ControlMethods

Passive ControlMethods

Semi-Active ControlMethods

Active - HybridControl Methods

Semi-Active HybridControl Methods


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DUCTILE DETAILING METHOD FOR EARTHQUAKERESISTANCE

Ductility of structure is enhanced by proper ductile detailing of

reinforcement.

Ductility can be achieved only through yielding of structural

members during earthquake.

Following the yielding, structure shows large structural and

non-structural damage.

Performance of intended ductile structures have proved to be

unsatisfactory and far below expectation during past

earthquake.


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PASSIVE CONTROL METHODS

To enhance structural safety and integrity against earthquake Base-isolation is Most Promising Alternative .

Base isolation is Decoupling of Building by introducingLow Horizontal Stiffness Bearing between structure andfoundation.


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SUITABILITY OF BASE ISOLATION

The sub-soil does not produce a predominance of LongPeriod Ground Motion.

Structure is Fairly Squat and with sufficiently High ColumnLoad.

The site permits horizontal Displacements At The Base of The Order of 200 mm or More.

Lateral Loads Due to Wind are Less than approximately10% of the weight of structure.


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NEED FOR PRESENT STUDY

An empirical formula for time period for multi- storeystructure with N storeys is

T n = 0.1 N

Taking a look at response spectra curve given inIS:1893(PART 1): 2002


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Significant benefits of base isolation can be obtained in Low-Rise Structures (less than 10-storeys).

Tall structures have high time period, so they Attract LessEarthquake Force.

Despite of high flexibility following requirements haveattracted engineers to apply base-isolation to tall structures.

1. Comfort of occupants

2. When Contents of building are More Valuable thenbuilding itself.

3. High-precision factories and building with SensitiveEquipments.

4. Buildings that should remain Operational Immediately After Earthquake like hospitals, police-stations, tele-communication stations etc.


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LIMITATION OF BASE-ISOLATED TALL BUILDINGS

Susceptible To Resonance under long period groundmotion.

Area with Loose Soils produces Long Period GroundMotions.

Drift in tall flexible building might becomeUncontrollable .

Base-displacement Becomes Large so proper careshould be taken for connection and installation of services at base-isolation level.


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OBJECTIVE OF STUDY

To study performance of Segmental Building with LaminatedRubber Bearing under different Near Fault and Far Fault GroundMotion.

To verify Effectiveness Of Segmental Building compared toconventionally base-isolated system and fixed-base buildings.

To study performance of Segmental Building with Active-Hybrid Control System under different Near Fault and Far Fault Ground Motion.

To carry out parametric study and comparison of SegmentalBuilding With Active-Hybrid And Passive Control.


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2. LITRATURE REVIEW Number of papers have been published on Structural Control for TallBuildings . Excellent reviews being published on the control concepts and

applications are available in papers of Pan, Jain, Ariga, Matsagar etc.

PAN et al. (1995) investigated dynamic characteristic of SegmentalBuilding with Isolator with Optimum Parameters Subjected to N-S ElCentro Ground Motion and carried out comparision with fixed base andbase isolated building. it was found that segmantal building possesed ability

to Isolate Building Similar to Base Isolated Building and AlsoSignificantly Reduces Overall Displacement.

PAN et al. (1998) investigated response of Segmental Building to aRandom Seismic Excitation and concluded that segmental buildingdecouple building from ground excitation and considerable Reduction inDisplacement at Base Level Compared Base Isolated Building .

JAIN et al. (2004) stiffened superstructure with 10, 14 & 20 storeys weresubjected to different earthquake motion and observed ConsiderableReduction In Maximum Roof Acceleration & Maximum Storey Drift but storey shear and base displacement increased due to stiffening.


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ARIGA et al. (2006) investigated the Resonant Behaviour of Base-isolatedHigh-Rise Building under long period ground motion induced by surfacewaves and concluded that friction type isolators have remarkable

characteristics unfavorable to long period ground motion.

JANGID (2004) discussed problem of sliding structure which is discontinuousone as different set of equation with Varying Force Function are Requiredfor Sliding and Non-sliding Phase . Comparative study of conventionalmodel and hysteretic model of frictional force is carried out.

PRANESH et al. (2002) carried out parametric study of Multistory Buildingwith VFPI and found it Stable During Low and Medium Intensity Excitationand Fails Safe During High Intensity Ground Motion .

SPENCER et al. (2003) discussed the recent development in smart controlsystems and discussed advantages of semi-active devices due to theirmechanical simplicity, low power requirement and large controllable forcecapacity.


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Dutta (2003) ) gave state-of-art review of Active Controlled Structures .Theoretical backgrounds of different active control schemes , Important Parametric Observations on Active Structural Control, Limitations andDifficulties in Their Practical Applications were discussed.

CONCLUDING REMARK

The review of literature revels that Structural Control Technique IsInevitable Earthquake Resistant Design Method . It also gives idea about performance and Advantages Of Passive, Active And Semi-active controlsystems. Some papers shows that despite of longer time period Base-isolation Can Still Be Implemented In Tall Buildings and also discussabout Resonant Behavior of isolated structures under long period ground

motion


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3. SEGMENTAL BUILDING It is extension of the conventional base isolation

technique with a Distributed Flexibility In TheSuperstructure.

SEGMENTAL BUILDING BASE ISOLATED BUILDING FIXED BASE BUILDING


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As the Building Is Divided In Number Of Segments this type of building is known as segmental building.

Each Segment is Comprise of Few Storey and is Interconnectedby Vibrational Isolator system.

Absorption and dissipation of earthquake energy are AffordedBy Isolators At All Level rather than at base-isolator level only.

Order of Displacement Demand at Base Level is Less than solelybase-isolated building.


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PRACTICAL APPLICATION OF SEGMENTAL BUILDING

MODEL OF BASE-ISOLATED BUILDING OVER RAILWAYPLATFORM (CHINA)


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SHIODOME SUMITOMO BUILDING(JAPAN)


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DONG-II HIGH VILL CITY BUILDING(KOREA)ISOLATORS ARE INSTALLED AT 8 STOREY ABOVE PARKING


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4. FLOW CHART FOR RESPONSE OFMULTI-DEGREE FREEDOM SYSTEM

INPUTS

Number Of Storeys

Mass

Stiffness

Damping Of Structure

Properties Of Isolators

Ground Excitation


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Stodola Vianellos Method is Adopted for Eigen

Value and Eigen Vector Solution.

Super-Position of Modal Damping Matrix is Used

for Construction of Damping Matrix.

Newmarks Step-By-Step Integration Method assumingLinear Variation in Acceleration is Adopted For TimeHistory Analysis.


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READ INPUT DATA

FORM DIAGONALMASS MATRIX

FORMATION OF STIFFNESS MATRIX

FORMATION OF DAMPING MATRIX


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ASSIGNBASE ISOLATOR PROPERTIES

NUMERICAL EVALUATION OF DYNAMIC RESPONSE USINGSTEP BY STEP INTEGRATION TECHNIQUE

INTERPRETATION & COMPARISION OF RESPONSE


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Program Verification For Fixed Base Building

Program Verification For Base-isolated Building

Program Verification For Segmental Building


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PROGRAM VERIFICATION FOR FIXED BASE BUILDING

Five-Storey Shear Frame (Chopra, A. K. (2000). Dynamics Of Structures:Theory And Applications To Earthquake Engineering, 2nd Ed., Prenticehall,

Upper Saddle River, N.J.)

DATA

Storey Height (h) = 12

Mass (m) = 100 kips/g

Storey Stiffness (k) = 31.54 kips/in.

Damping Ratio ( ) = 5%

Subjected To N-S Component Of EL CENTROGround Motion


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Mode of Vibration Program Output Chopra

First 1.9996 2.0000

Second 0.6850 0.6852

Third 0.4346 0.4346

Fourth 0.3383 0.3383

Fifth 0.2966 0.2966

Response Program Output Chopra

Peak roof displacement (inch) 6.841 6.847Peak base shear (kips) 73.179 73.278

Peak fifth storey shear (kips) 35.083 35.217

Peak base overturning moment (kips-ft) 2589.2 2593.2

TABULAR COMPARISON

Natural Time Period


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GRAPHICAL COMPARISON

ROOF DISPLACEMENT FROM PROGRAM

ROOF DISPLACEMENT FROM CHOPRA


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BASE SHEAR FROM PROGRAM

BASE SHEAR FROM CHOPRA


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ROOF SHEAR FROM PROGRAM

ROOF SHEAR FROM CHOPRA


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BASE-OVER TURNING MOMENT FROM PROGRAM

BASE-OVER TURNING MOMENT FROM CHOPRA


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PROGRAM VERIFICATION FOR BASE-ISOLATED BUILDING

Five Storey Base-Isolated Shear Frame (Matsagar, V. A. and Jangid, R. S.(2003) Seismic Response of Base-Isolated Structures During Impact with

Adjacent Structures Engineering Structures, Elsevier, 25, 2003.)

Type Of Isolator LRB Superstructure Time Period 0.5 SEC

Base-isolator Time Period 2.0 SEC Superstructure Damping Ratio 0.02 Base-isolator Damping Ratio 0.10 Mass Ratio (M B / M) 1.0

Subjected To N00E Component Of 1989 LOMAPRIETA Earthquake Recorded At LOS GATOSPRESENTATION CENTER


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BEARING DISPLACEMENT FROM PROGRAM

BEARING DISPLACEMENT FROM MATSAGAR


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TOP FLOOR ACCELERATION FROM PROGRAM

TOP FLOOR ACCELERATION FROM MATSAGAR


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VERIFICATION OF PROGRAM FOR SEGMENTAL BUILDING (Pan, T. C., Ling, S. F. and Cui, W. (1995) Seismic Response of SegmentalBuildings Earthquake Engineering and Structural Dynamic , 24,1039-1048)

Number Of Storeys 16 Height Of Storey 3 m Number Of Storey In Segment 4 Modal Damping Ratio 5% N-S COMPONENT EL CENTRO EARTHQUAKE

Isolator PropertiesLEVEL OF ISOLATOR LATERAL STIFFNESS

10 8 N/m

Ground Level 1.11

Fourth Floor 12.9

Eighth Floor 6.76

Twelfth Floor 2.14


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PROPERTIES OF SEGMENT

STIFFNESS OF STOREY THROUGH OUT SEGMENT

LEVEL STIFFNESS (N/m)FIRST (BOTTOM MOST) 2.4 x 10 9

SECOND 1.29 x 10 9

THIRD 6.76 x 10 8

FOURTH TOP 3.15 x 10 8

MASS OF STOREY IN INDIVIDUAL SEGMENT

STOREY MASS(kg)

ISOLATED RAFT 2.52 x 10 5

INTERMEDIATE LEVELS 3.49 x 10 5

SEGMENT ROOF MASS 1.39 x 10 5


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TABULAR VERIFICATION OF NATURAL FREQUENCY (Hz)

Program Output 0.55 1.37 2.55 4.02 4.68

Pan et al. (1995) 0.54 1.35 2.48 3.92 4.61

FUNDAMENTAL MODE SHAPES

FIRST MODE SECOND MODE


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THIRD MODE FOURTH MODE



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5. ANALYSIS OF SEGMENTAL ,BASE-ISOLATED & FIXED-BASE BUILDING

Number Of Storeys 16 Height Of Storey 3 m Number Of Storey In Segment 4 Modal Damping Ratio 5%

Isolator Properties Segmental Building

LEVEL OF ISOLATOR LATERAL STIFFNESS10 8 N/m

Ground Level 1.51

Fourth Floor 2.76Eighth Floor 0.57

Twelfth Floor 3.15

Base-Isolated Building - 0.59 x 10 8 N/m


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GROUND MOTIONS CONSIDERED

Sr

No Type Earthquake

Record

Component

PGD

(cm)

PGV

(cm/s)

PGA

(g)

1Far

Fault

Motion

1999 Chi-Chi, Taiwan TCU 047 22.22 40.02 0.413

2 1979 Imperial Valley DELTA 352 19.02 33 0.351

3 1995 Kobe KAKOGAWA 090 9.6 27.6 0.345

4

NearFault

Motion

1999 Chi-Chi, Taiwan TCU 129 50.15 60 1.01

5 1979 Imperial Valley El-Cento Array # 8 32.32 54 0.602

6 1995 Kobe KJM 000 17.68 81.3 0.821


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Natural Frequencies (Hz)

Mode 1 Mode 2 Mode 3 Mode 4 Mode 5

F B Model 0.94 2.26 3.66 5.21 6.26

B I Model 0.49 1.55 2.90 4.43 5.64

S B Model 0.46 1.25 2.03 3.01 4.23

DYNAMIC PROPERTIES


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FUNDAMENTAL MODE SHAPES

0

10

20

30

40

50

0.0 0.2 0.4 0.6 0.8 1.0 1.2

Mode 1

H e i g h

t m

0

10

20

30

40

50

-1.8 -1.2 -0.6 0.0 0.6 1.2

Mode 2

H e i g h

t m

0

10

20

30

40

50

-1.2 -0.6 0.0 0.6 1.2

FBSBBI

Mode 3

H e i g h

t m

0

10

20

30

40

50

-8 -4 0 4 8

Mode 4

H e i g h

t m


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Reduction in Base Displacements

Type Earthquake SegmentalBuilding Base IsolatedBuilding %Difference

FarFault

Motion

Chi-Chi, Taiwan 0.0617 0.10635 41.98

Imperial Valley 0.06102 0.17152 64.42

Kobe 0.05483 0.2 72.59

NearFault

Motion

Chi-Chi, Taiwan 0.09887 0.17257 42.71

Imperial Valley 0.07338 0.223 67.09

Kobe 0.15858 0.285 44.36


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0

10

20

30

40

50

0.00 0.05 0.10 0.15 0.20

Peak Storey Displacement -1999 Chi-Chi FF

Displacementm

H e i g

h t m

0

10

20

30

40

50

0.00 0.12 0.24 0.36

Peak Storey Displacement -1995 Kobe FF

FBSBBI

Displacementm

H e i g

h t m

0

10

20

30

40

50

0.0 0.1 0.2 0.3

Peak Storey Displacement -1979 Imperial Valley FF

Displacementm

H e i g h

t m

42

Peak Displacement

Response Under Far Fault Ground Motions


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Peak Displacement Response Under Near Fault

Ground Motions

0

10

20

30

40

50

0.0 0.1 0.2 0.3

Peak Storey Displacement -1999 Chi-Chi NF

Displacementm

H e i g

h t m

0

10

20

30

40

50

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Peak Storey Displacement -1995 Kobe NF

Displacementm

H e i g h

t m

0

10

20

30

40

50

0.00 0.15 0.30 0.45

Peak Storey Displacement -1979 Imperial Valley NF

FBSBBI

Displacementm

H e i g h

t m


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Top - Storey Acceleration Response

EarthquakeSegmentalBuilding

Base IsolatedBuilding % Difference

Far Fault

CHI-CHI FF 0.43288 0.36227 -19.49

IMP VALL FF 0.33166 0.32156 -3.14

KOBE FF 0.33588 0.38119 11.89

Near Fault

CHI-CHI NF 0.60602 0.40546 -49.46

IMP VALL NF 0.47897 0.47121 -1.65

KOBE NF 1.09837 0.89199 -23.14


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Peak Absolute AccelerationResponse Under

Far Fault Ground Motions

0

10

20

30

40

50

0.0 0.2 0.4 0.6 0.8 1.0

Peak Storey Acceleration - 1999 Chi-Chi FF

FBSBBI

Absolute acceleration

H e i g h

t m

0

10

20

30

40

50

0.0 0.3 0.6 0.9

Peak Storey Acceleration - 1979 Imperial Valley FF

Absolute acceleration (m/s2)

H e i g h

t m

0

10

20

30

40

50

0.00 0.25 0.50 0.75 1.00

Peak Storey Acceleration - 1995 Kobe FF


H e i g h

t m


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0

10

20

30

40

50

0.0 0.8 1.6 2.4

Peak Storey Acceleration - 1999 Chi-Chi NF


H e i g h

t m

0

10

20

30

40

50

0.0 0.5 1.0 1.5

Peak Storey Acceleration - 1979 Imperial Valley NF

FBSBBI


H e i g h

t m

0

10

20

30

40

50

0.0 0.8 1.6 2.4 3.2

Peak Storey Acceleration - 1995 Kobe NF


H e i g

h t m

46

Peak Absolute Acceleration

Response UnderNear Fault Ground Motions


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Reduction in Base-Shear

EarthquakeSegmentalBuilding

Base IsolatedBuilding

%Difference

Far Fault

CHI-CHI FF 7.76E+06 7.23E+06 -7.34

IMP VALL FF 9.21E+06 1.17E+07 21.25KOBE FF 8.28E+06 1.36E+07 39.13

NearFault

CHI-CHI NF 1.49E+07 1.17E+07 -27.61

IMP VALL NF 1.11E+07 1.52E+07 27.10

KOBE NF 2.39E+07 1.94E+07 -23.43


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0

10

20

30

40

50

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Peak Storey Shear - 1999 Chi-Chi FF

Storey Shear (N) X106

H e i g h

t ( m

)

0

10

20

30

40

50

0 2 4 6 8 10 12 14 16 18

Peak Storey Shear - 1979 Imperial Valley FF


H e i g h

t ( m

)

0

10

20

30

40

50

0 2 4 6 8 10 12 14 16 18 20

Peak Storey Shear - 1995 Kobe FF

FBSBBI


H e i g h

t ( m

)

48

Peak Storey Shear

Response UnderFar Fault Ground Motions


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Peak Storey Shear


0

10

20

30

40

50

0 2 4 6 8 10 12 14 16 18 20 22 24 26

Peak Storey Shear - 1999 Chi-Chi NF

FBSBBI


H e i g h

t ( m

)

0

10

20

30

40

50

0 2 4 6 8 10 12 14 16 18

Peak Storey Shear - 1979 Imperial Valley NF


H e i g h

t ( m

)

0

10

20

30

40

50

0 10 20 30 40 50

Peak Storey Shear - 1995 Kobe NF


H e i g h t ( m )


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Reduction in Base-Over Turning Moment

Earthquake SegmentalBuilding

Base IsolatedBuilding

%Difference

Far Fault

CHI-CHI FF 1.60E+08 2.49E+08 35.82

IMP VALL FF 2.62E+08 3.17E+08 17.24

KOBE FF 2.64E+08 3.62E+08 27.07

Near

Fault

CHI-CHI NF 2.96E+08 3.20E+08 7.41

IMP VALL NF 3.53E+08 3.98E+08 11.36

KOBE NF 4.69E+08 6.30E+08 25.60


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0

10

20

30

40

50

0 5 10 15 20 25 30 35 40

Peak Storey Overturning Moment - 1999 Chi-Chi FF

Over Turning Moment kN-m X10 7

H e i g h

t m

0

10

20

30

40

50

0 5 10 15 20 25 30 35 40 45

Peak Storey Overturning Moment - 1979 Imperial Valley FF

FBSBBI

Over Turning Moment (N-m) X10 7

H e i g h

t ( m

)

0

10

20

30

40

50

0 11 22 33 44 55

Peak Storey Overturning Moment - 1995 Kobe FF

Over Turning Moment (N-m) X10 7

H e i g h

t ( m

)

51

Peak Over TurningMoment Response UnderFar Fault Ground Motions


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0

10

20

30

40

50

0 5 10 15 20 25 30 35 40 45 50 55 60 65

Peak Storey Overturning Moment - 1999 Chi-Chi NF

FBSBBI

Over Turning Moment (N-m) X107

H e i g h

t ( m

)

0

10

20

30

40

50

0 9 18 27 36 45

Peak Storey Overturning Moment - 1979 Imperial Valley NF


H e i g h

t ( m

)

0

10

20

30

40

50

0 20 40 60 80 100 120 140 160

Peak Storey Overturning Moment - 1995 Kobe NF


H e i g h

t ( m

)

52

Peak Over TurningMoment Response Under

Near Fault Ground Motions


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-0.10 -0.05 0.00 0.05 0.10

-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

-0.20 -0.15 -0.10 -0.05 0.00 0.05 0.10 0.15 0.20

-0.2

-0.1

0.0

0.1

0.2

-0.20 -0.15 -0.10 -0.05 0.00 0.05 0.10 0.15 0.20

-0.2

-0.1

0.0

0.1

0.2

-0.2 -0.1 0.0 0.1 0.2 0.3-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

-0.2 -0.1 0.0 0.1 0.2-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3-0.4

-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

0.4

Chi - Chi FF

F o r c e

Displacement

Chi - Chi NF

F o r c e

Displacement

Imperial Valley FF

F o r c e

Displacement

Imperial Valley NF

F o r c e

Displacement

Kobe FF

F o r c e

Displacement

Kobe NF

F o r c e

Displacement m

53

Hysteresis Damping in Base-Isolated Building


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-0.014 -0.007 0.000 0.007

-0.09

-0.06

-0.03

0.00

0.03

0.06

-0.10 -0.05 0.00 0.05 0.10

-0.10

-0.05

0.00

0.05

0.10

-0.02 -0.01 0.00 0.01 0.02 0.03-0.14

-0.07

0.00

0.07

0.14

-0.08 -0.04 0.00 0.04 0.08-0.18

-0.09

0.00

0.09

0.18

12th Storey Isolator

F o r c e

Displacement(m)

8th Storey Isolator

F o r c e

Displacement(m)

4th Storey Isolator

F o r c e

Displacement (m)

Base-Isolator

F o r c e

Displacement (m)

Hysteresis Damping in Segmental Building

-0.04 -0.02 0.00 0.02 0.04

-0.2

-0.1

0.0

0.1

0.2

0.3

-0.2 0.0 0.2 0.4-0.30

-0.15

0.00

0.15

0.30

-0.06 -0.03 0.00 0.03 0.06

-0.2

0.0

0.2

0.4

-0.2 -0.1 0.0 0.1-0.50

-0.25

0.00

0.25

0.50

12th Storey Isolator

F o r c e

Displacement (m)

8th Storey Isolator

F o r c e

Displacement (m)

4th Storey Isolator

F o r c e

Displacement (m)

Base-Isolator

F o r c e

Displacement (m)

1999 Chi-Chi TCU 047

Far Fault

1995 Kobe KJM 000

Near Fault


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4. ACTIVE-HYBRID CONTROL OFSEGMENTAL BUILDING

Combination of Active Control Devices and Passive ControlDevices is known as Active-hybrid Control

Actuators are installed at segment level along withLaminated Rubber Bearings in segmental building

Pole Placement Technique is used as Control Algorithm forgeneration of control forces.

ACTIVE CONTROL OF STRUCTURES


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CLOSED-LOOP

SYSTEM

OPEN-LOOP

SYSTEM

56

ACTIVE CONTROL OF STRUCTURES

STRUCTURESTRUCTURAL

RESPONSE

SENSORS

EXTERNAL

EXCITATIONS

SENSORS

COMPUTATION OF

CONTROL FORCES

ACTUATORS

CONTROL

FORCES


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When Only Structural Response Variables are measured thecontrol configuration are known as Closed-Loop or Feed-Back

System.

When O nly Excitation are measured the control configuration areknown as Open-Loop or Feed-Front System.

When information of both Response Quantities and ExternalExcitation are measures for control design it is known as Closed-Open-Loop System.

System used in present study is Closed-Loop System.

PROBLEMS IN REAL-TIME APPLICATIONS


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Modeling error

Time Delay

Limited Sensors and Controllers

Parameter Uncertainty and System Identification

Discrete Time Control

Reliability

Cost-Effectiveness and Hardware Requirements

PROBLEMS IN REAL TIME APPLICATIONS


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EQUATION OF MOTION OF CONTROLLED STRUCTURE

D Is Location Matrix

u Is Control Force Vector AndIs Proportional To , x and Ground Excitation

K 1 , C1 , E Are Time Independent Matrix

Control Depends On How K 1 And C1 Are Obtained

STATE SPACE EQUATION


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STATE-SPACE EQUATION

Using State-space Second Order Differential Equation Of MotionIs Converted In First Order Equation

Let Equation Of Motion Be


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State-space Equation For Controlled Motion Will Be

Where G Is Gain Matrix And D Is Position Vector

ACTIVE CONTROL ALGORITHMS


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ACTIVE CONTROL ALGORITHMS

Number of active algorithms are developed for finding controlforce u (t).

Most of algorithm derive control force by minimizing the normof some response therefore termed as Optimal ControlAlgorithm.

The derived control forces are linear functions of state vectorhence are also known as Linear Optimal Control Algorithm.

There are also some algorithm that are not based on optimalcriterion but on stability criterion or some other considerations.

Also control algorithms have control forces in terms non-linearfunctions of state vector.


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Pole Placement Technique / Pole Assignment Technique Classical Linear Optimal Control / Linear Quadratic Regulator

(LQR)

Instantaneous Optimal Control Closed Open Loop Control

Independent Modal Space Control (IMSC)

Bounded State Control

And some other FUZZY Controls and Predictive Controls.

CONTROL ALGORITHMS

POLE-PLACEMENT TECHNIQUE


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Q

State-Space Equation For Controlled Motion

Eigen values of A are poles of uncontrolled systems.Eigen values of are poles of uncontrolled systems.

The poles of system is given by

S - PLANE


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Unstable Region Stable Region

Desired poles are selected such that they are on left side of uncontrolled pole.

Choice of desired poles depends upon percentage of controlforces and amount of peak control force required.

After selecting poles of controlled system the Gain matrix G isobtained to generate control forces.

Real

Imaginary

FEEDBACK GAIN MATRIX


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Ackermanns formula is used to calculate G Feedback Gain Matrix.

MATLAB has standard programs for calculation of gain matrix i.e.

acker - for Ackermanns formula for SDOF systems

place for MDOF systems.

For calculating G matrix A, B, and J Desired Pole Matrix arerequired e.g.

G = acker(A,B,J)

G = place(A,B,J)

COMPUTATION OF RESPONSE


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First order linear differential equation of motion

Equation is solved using Linear Time Invariant Simulation functionof MATLAB i.e. lsim

On solving equation we get displacement and velocity responsesof building.

VERIFICATION OF PROGRAM FOR ACTIVE CONTROL


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USING POLE PLACEMENT TECHNIQUE Five-Storey Shear Frame With Actuator At Top Storey (Dutta, T. K.(2010). Seismic Analysis of Structures , John Wiley & Sons (Asia) Pte. Ltd.)

DATA

Storey Height (h) = 4 m

Mass (m) = 150000 kg

Storey Stiffness (k) = 200000 kN/m.

Damping Ratio ( ) = 5%

Actuators are installed at top storey

Subjected to N-S Component of EL CENTRO ground motion


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Uncontrolled Poles Desired Poles

-6.260 + 71.858 i -10 + 71 i

-6.260 - 71.858 i -10 - 71 i

-5.173 + 64.864 i -10 + 70 i

-5.173 - 64.864 i -10 - 70 i

-3.416 + 51.527 i -10 + 30 i

-3.416 - 51.527 i -10 - 30 i

-1.658 + 33.113 i -10 + 12 i

-1.658 - 33.113 i -10 - 12 i-0.571 + 11.410 i -22 + 0.4 i

-0.571 - 11.410 i -22 - 0.4 i

DISPLACEMENTS OF FIFTH STOREY


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0 5 10 15 20 25 30-0.08

-0.06

-0.04

-0.02

0.00

0.02

0.04

0.06

0.08

Controlled Response Uncontrolled Response

D i s p l a c e m e n t

( m )

Time (s)

DISPLACEMENTS OF FIRST FLOOR


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0 5 10 15 20 25 30-0.03

-0.02

-0.01

0.00

0.01

0.02

0.03

Controlled Response Uncontrolled Response

D i s p l a c e m e n t ( m

)

Time (s)


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Comparison of Peak Base Displacement (cm)

Type EarthquakeActiveControl

PassiveControl

%Differenc

e

Far

Field Motion

1999 Chi-Chi, Taiwan 5.11 6.17 17.18

1979 Imperial Valley 4.31 6.10 29.341995 Kobe 3.45 5.48 37.04

Near

Fault

Motion

1999 Chi-Chi, Taiwan 8.15 9.89 17.59

1979 Imperial Valley 5.42 7.34 26.16

1995 Kobe 12.13 15.86 23.52


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Comparison of Roof Displacement (cm)

Type EarthquakeActive

Control

Passive

Control

%

Differenc

e

FarField

Motion

1999 Chi-Chi, Taiwan 8.66 17.66 50.961979 Imperial Valley 18.92 28.82 34.35

1995 Kobe 14.33 30.05 52.31

Near

Fault

Motion

1999 Chi-Chi, Taiwan 20.19 29.52 31.61

1979 Imperial Valley 21.62 40.10 46.08

1995 Kobe 31.29 48.52 35.51

Comparison of Peak Storey Displacement - 1999 Chi-Chi FF Comparison of Peak Storey Displacement - 1979 Imperial Valley FF


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0

10

20

30

40

50

0.00 0.03 0.06 0.09 0.12 0.15 0.180

10

20

30

40

50

0.00 0.05 0.10 0.15 0.20 0.25 0.30

0

10

20

30

40

50

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35

p y p

Displacement (m)

Controlled Uncontrolled

H e i g h

t ( m )

p y p p y

Displacement (m)

H e i g h

t ( m )

Comparison of Peak Storey Displacement - 1995 Kobe FF

Displacement (m)

H e i g h

t ( m

)

Peak Storey Displacement Response Under



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0

10

20

30

40

50

0.00 0.05 0.10 0.15 0.20 0.25 0.300

10

20

30

40

50

0.00 0.06 0.12 0.18 0.24 0.30 0.36 0.42

0

10

20

30

40

50

0.0 0.1 0.2 0.3 0.4 0.5

Comparison of Peak Storey Displacement - 1999 Chi-Chi NF

Displacement (m)


H e i g h

t ( m

)

Comparison of Peak Storey Displacement - 1979 Imperial Valley NF

Displacement (m)

H e i g h

t ( m

)

Comparison of Peak Storey Displacement - 1995 Kobe NF

Displacement (m)

H e i g h

t ( m

)Peak Storey Displacement



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Comparison of Peak Base Shear X10 6 (N)


Control

Passive

Control

%

Difference

Far FieldMotion

1999 Chi-Chi, Taiwan 7.72 9.32 17.17

1979 Imperial Valley 6.51 9.22 29.39

1995 Kobe 5.21 8.29 37.15

Near

Fault

Motion

1999 Chi-Chi, Taiwan 12.30 14.93 17.62

1979 Imperial Valley 8.19 11.08 26.08

1995 Kobe 18.32 23.91 23.38

50 50

1999 Chi-Chi - TCU 047

Controlled

1979 Imperial Valley - DELTA 352


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0

10

20

30

40

0 2 4 6 8 10 0

10

20

30

40

0 2 4 6 8 10

0

10

20

30

40

50

0 2 4 6 8 10

Uncontrolled

Storey Shear X10 6 (N)

H e i g h

t ( m

)


H e i g h

t ( m )

1995 Kobe - KAKOGAWA 090

Storey Shear X106

(N)

H e i g h

t ( m

)

Peak Storey ShearResponse Under


50 501999 Chi-Chi - TCU 129 1979 Imperial Valley - El-Centro Array#8


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0

10

20

30

40

0 4 8 12 160

10

20

30

40

0 3 6 9 12

0

10

20

30

40

50

0 5 10 15 20 25


H e i g h

t ( m )


H e i g h

t ( m )

1995 Kobe - KJM 000


H e i g h

t ( m )

Peak Storey ShearResponse Under


Comparison of Peak


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Comparison of Peak

Base Over-Turning MomentX10 8 (N-m)


Control

Passive

Control

%

Differenc

e

Far Field

Motion

1999 Chi-Chi, Taiwan 0.93 1.60 41.88

1979 Imperial Valley 1.64 2.62 37.40

1995 Kobe 1.34 2.64 49.24

NearFault

Motion

1999 Chi-Chi, Taiwan 2.46 2.96 16.891979 Imperial Valley 2.01 3.53 43.06

1995 Kobe 2.71 4.69 42.22

1999Chi Chi TCU047


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0

10

20

30

40

50

0 3 6 9 12 15 180

10

20

30

40

50

0 7 14 21 28

0

10

20

30

40

50

0 5 10 15 20 25 30

1999 Chi-Chi - TCU 047


Over-Turning Moment X10 7 (N-m)

H e i g h t ( m )

1979 Imperial Valley - DELTA 352

Over Turning Moment X10 7 N-m

H e i g h t ( m )

1995 Kobe - Kakogawa 090


H e i g h t ( m )

Peak Over TurningMoment Response UnderFar Fault Ground Motions

50 501999 Chi-Chi - TCU 129 1979 Imperial Valley - El-Centro Array#8


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0

10

20

30

40

0 5 10 15 20 25 300

10

20

30

40

0 6 12 18 24 30 36

0

10

20

30

40

50

0 10 20 30 40 50


H e i g h

t ( m )


H e i g h

t ( m )

1995 Kobe - KJM 000


H e i g h

t ( m )

Peak Over TurningMoment Response Under



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Peak Control Force

Type EarthquakeControl Force

X103 (kN)

Far Field Motion1999 Chi-Chi, Taiwan 8.661979 Imperial Valley 18.92

1995 Kobe 14.33

Near Fault Motion

1999 Chi-Chi, Taiwan 20.19

1979 Imperial Valley 21.621995 Kobe 31.29

2 1.51999 Chi-Chi - TCU 047 1979 Imperial Valley - DELTA 352


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0 19 38 57 76 95-2

-1

0

1

0 20 40 60 80 100-1.5

-1.0

-0.5

0.0

0.5

1.0

0 11 22 33 44-1.4

-0.7

0.0

0.7

1.4

F o r c e

( N )

X 1 0

6

Time (s)

F o r c e

( N )

X 1 0

6

Time (s)

1995 Kobe - Kakogawa 090

F o r c e

( N ) X 1 0

6

Time (s)

Control Force HistoryUnder


32

1999 Chi-Chi - TCU 129 1979 Imperial Valley - El-Centro Array#8


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0 19 38 57 76 95-3

-2

-1

0

1

2

0 10 20 30 40-2

-1

0

1

0 10 20 30 40 50-4

-2

0

2

4

F o r c e

( N ) X 1 0

6

Time (s)

F o r c e

( N ) X 1 0

6

Time (s)

1995 Kobe - KJM 000

F o r c e

( N )

X 1 0

6

Time (s)

Control Force HistoryUnder


Compariso

n Of Isolator Displacement Subjected To1999 Chi Chi TCU 047


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30 60-0.064

-0.032

0.000

0.032

0.064

30 60-0.026

-0.013

0.000

0.013

0.026

30 60-0.10

-0.05

0.00

0.05

0.10

30 60-0.016-0.008

0.000

0.008

0.016

Isolator Displacement at Ground Level

D i s p l a c e m e n

t ( m

)

Time (s)

Isolator Displacement at 4 th Storey


t ( m

)

Time (s)



t ( m

)

Time (s)


Uncontrolled Controlled


t ( m

)

Time (s)


Compariso

n Of Isolator Displacement Subjected To1995 KOBE KJM000


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10 20-0.150

-0.075

0.000

0.075

0.150

10 20-0.06-0.04-0.020.000.020.040.06

10 20-0.26

-0.13

0.00

0.13

0.26

10 20-0.04

-0.02

0.00

0.02

0.04

Isolator Displacement at Ground Level


t ( m )

Time (s)


D

i s p l a c e m e n

t ( m )

Time (s)



t ( m )

Time (s)


Uncontrolled Controlled

D i s p l a c e m

e n t ( m )

Time (s)

1995 KOBE KJM000

Comparison Of Hysteresis Damping


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5. CONCLUSION & FUTURE SCOPE


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Segmental Building With Passive Control Natural Time Period of segmental building is Higher compared to other soattracted earthquake force is lower

Reduction of Average 56% in Peak Base Displacement is obtained insegmental building compared to base-isolated

Increase of 14 % in Peak Roof Acceleration is noticed in segmentalbuilding compared to base isolated building but it is remarkably lowcompared to fixed-base building.

Average 5 % Reduction in Storey Shear response is seen in segmentalbuilding compared to base-isolated building under set of near fault and farfault ground motions.

Average Reduction of 21 % is Seen in Peak Base Over-Turning Moment in segmental building compared to base isolated building.

A Large Amount of Energy is Dissipated at Different Levels in segmentalbuilding when compared to base-isolated building.

Segmental Building With Active-Hybrid Control


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Average Reductions of 25% in Peak Base Displacement while 42 % inpeak roof displacement is seen in controlled building over uncontrolled

building subjected to both near fault and far fault ground motion. Reduction of Average 23 % in Peak Base Shear is seen on controlledbuilding over uncontrolled building

Reduction of Average 21 % in Peak Base Overturning Moment is seen

in controlled building compared to uncontrolled building Due to reduced displacements and introduction of control force Very Less

Amount of Energy is Dissipated by Isolators in Controlled Building when compared to uncontrolled building.

Based on above observations, it is concluded that SegmentalBuilding Appears to Hold the Promise of Extending Passive and Active-hybrid Control Technique to Mid-rise Buildings alsowhich is still restricted to low-rise buildings.

Future Scope


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Comparative study on response of segmental building withVariation of Number of Storeys in Each Segment.

Response of segmental building with Other Friction Base andElastomeric Isolators under different ground motion.

Response of segmental building with passive and active control

under Action of Wind Load . Response of segmental building with Semi-Active And Hybrid- Aemi-Active Control Systems under seismic and wind loads.

Experimental evaluation of seismic performance of segmentalbuilding with passive and active control.

REFERENCES


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Ariga, T., Kanno, Y., Takewaki, I.(2006) Resonant Behaviour of Base-Isolated High-Rise Buildings Under Long-Period Ground Motions Journal of the Structural Design of Tall and Special Buildings , 15, 325-338.

Chopra, A K Dynamics of Structures Pearson Education. Inc.

Clough, R. W. & Penzien, J. Dynamics of Structures Mc Graw Hill, Inc.

Craig, R. R. Jr. Structural Dynamics John Wiley & Sons

Deb, S. K. (2004) Seismic Base Isolation An Overview Special Section:Geotechnics and Earthquake Hazards; Current Science, 87.

Dutta, T. K. Seismic Analysis of Structures , John Wiley & Sons (Asia) Pte.Ltd

Hong, W. K., Kim, H. C. (2004) Performance of a multi-story structurewith a resilient-friction base isolation system Computers and Structures ,82, 2271-2283

Jain, S. K. & Thakkar, S. K. (2004) Effect of Super Structure Stiffening On


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, , ( ) p gBase Isolated Tall Building I E (I) Journal, 85,142-148.

Jangid, R. S. (2004) Computational Numerical Models for Seismic

Response of Structure Isolated By Sliding Systems Structural Control and Health Monitoring.

Kelly, J. M. (1986) Aseismic base isolation: review and bibliography Journal of soil Dynamics and Earthquake Engineering, 5, 202-216.

Matsagar, V. A. and Jangid, R. S. (2003) Seismic Response of Base-Isolated Structures During Impact With Adjacent Structures Engineering Structures, Elsevier , 25, 2003.

Pranesh, M. and Sinha, R. (2000) VFPI: An Isolation Device for A SeismicDesign Journal of Earthquake Engineering and Structural Dynamics , 29, 603-

627. Pranesh, M. and Sinha, R. (2002) Earthquake Resistance Design of Structures using the Variable Frequency Pendulum Isolator ASCE , 128,870-880.

Mukhopadhyay, M. Vibrations, Dynamics & Structural Systems Oxford &


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IHB Publishing Co. Pvt. Ltd.

Pan, T. C., Ling, S. F. and Cui, W. (1995) Seismic Response of Segmental

Buildings Earthquake Engineering and Structural Dynamic , 24,1039-1048. Pan, T. C., Cui, W. (1998) Response of Segmental Buildings To RandomSeismic Motions Iset Journal of Earthquake Technology, 35, 378.

Paz, M. Structural Dynamics Van Nostrand Reinhold Company, Inc.

Soni, D. P., Mistry, B. B., Jangid, R. S. and Panchal, V. R. (2010) SeismicResponse of The Double Variable Frequency Pendulum Isolator Structural Control and Health Monitoring .

Soni, D. P., Mistry, B. B. and Panchal, V. R. (2010) Behaviour of asymmetric

building with double variable frequency pendulum isolator Journal of Structural Engineering and Mechanics , 34, 61-84.

Soong, T. T., (1990) Active Structural Control: Theory and Practice Longman Scientific & Technical .

Soong, T. T., Costantinou, M. C., (1994) Passive And Active Structural


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Vibration Control in Civil Engineering Springer Verlag Wien New-York .

Spencer, B. F. Jr., Nagrajaiah, S., (2003) State of the Art of Structural

Control Springer Verlag Wien New-York .


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