CIVE 790-670

Prepared by Dr. F. Necati Catbas

CAD Drawings: Visualize, Conceptualize

60

DATA-INFORMATION-KNOWLEDGEData Integration, On-line Detection, WarehousingDisplay, Data Fusion, Data Mining, Correlation, Neural-NetDecision and Management Applications

ANALYSISAnalytical Modeling: Numerical, Geometric, Statistical/Stochastic, Calibration, SimulationPrediction

EXPERIMENTLoad Test: Static, DynamicLocal: NDE, Material TestLong Term Monitoring: Intermittent, Continuous, Integrated, Real Time

Survey of The Bridge: Observe, Measure

Win

d S

pee

d (m

ph

)

Structural and Loading Systems Identification

AD

E

Time12/21/98 12:00 AM

12/21/98 12:00 PM

12/22/98 12:00 AM

12/22/98 12:00 PM

12/23/98 12:00 AM

12/23/98 12:00 PM

10

20

30

40

50

60

30

210

60

240

90

270

120

300

150

330

180

0

11.36 mph

22.72 mph

34.08 mph

45.44 mph

56.8 mph

PA

NJ

12/22/98

General Tasks• Preparations

– Inspect grid, obtain existing models, review of material, – Determine damage scenarios– Number of tests and sequence

• Dynamic Test – Instrument the grid w/ accels– Conduct ambient, impact and forced excitation test

• Load Test– Install SWP sensors– Prepare Optim for testing– Prepare actuators

• Finite Element Modeling– Obtain model and take measurements, improve/create FE model

• Data Processing– Dynamic test data– Load test data– FE simulations– Correlations

• Documentation and Archival– Raw data– Image documentation of the grid, tests, equipment etc

To Do List for the Team

• April 24-26– Preparations– Dynamic test

instrumentation – SWP installation– Get FE Model– Decide & plan for damage

scenarios– Logistics for actuator

testing

• April 27- May 3– FEM preparation– Prepare VIX and Optim– Finish SWP installation– Conduct

• Ambient, forced and impact test

– Conduct load • With weights• With actuators after

moving

– Preliminary simulations

To Do List for the Team

• May 4 – 10– Data Processing

• Dynamic test• Load test• FE simulations

– Correlations of test results with FE Model simulations

– Induce damage

• May 11 – 17– Conduct

• Ambient, forced and impact test

– Conduct load • With weights• With actuators after

moving

– Data Processing– Experimental-

Analytical correlations

To Do List for the Team

• May 18 – 24– Data processing– Model calibration

• May 25 – 30– Final report– Documentation

XY

Z

123123123

123123123123123

123123123

123123123

123123123123123

123123123

0.783

0.734

0.685

0.636

0.587

0.538

0.49

0.441

0.392

0.343

0.294

0.245

0.196

0.147

0.0979

0.049

0.

V1L4C1

Output Set: Mode 1 5.998412 HzDeformed(0.783): Tota l Transla tionContour: Tota l Transla tion

Preliminary FEM = 5.99 HzImpact Modal Test = 5.04 HzAmbient Vib. Test = 5.05 Hz

First Mode of the Grid (Bending Mode)

XY

Z

123123123

123123123123123

123123123

123123123

123123123123123

123123123

1.202

1.127

1.052

0.976

0.901

0.826

0.751

0.676

0.601

0.526

0.451

0.376

0.3

0.225

0.15

0.0751

0.

V1L4C1

Output Set: Mode 2 7.880329 HzDeformed(1.202): Tota l Transla tionContour: Tota l Transla tion

Second Mode of the Grid (Torsional Mode)

Preliminary FEM = 7.88 HzImpact Modal Test = 7.79 HzAmbient Vib. Test = 7.73 Hz

XY

Z

123123123

123123123123123

123123123

123123123

123123123123123

123123123

0.81

0.76

0.709

0.658

0.608

0.557

0.506

0.456

0.405

0.355

0.304

0.253

0.203

0.152

0.101

0.0506

0.

V1L4C1

Output Set: Mode 3 19.6758 HzDeformed(0.81): Tota l Transla tionContour: Tota l Transla tion

Preliminary FEM = 19.68 HzImpact Modal Test = 17.59 HzAmbient Vib. Test = 17.26 Hz

Third Mode of the Grid (Asymmetric Bending Mode)

XY

Z

123123123

123123123123123

123123123

123123123

123123123123123

123123123

1.158

1.086

1.013

0.941

0.868

0.796

0.724

0.651

0.579

0.507

0.434

0.362

0.289

0.217

0.145

0.0724

0.

V1L4C1

Output Set: Mode 4 24.701 HzDeformed(1.158): Total Transla tionContour: Total Transla tion

Fourth Mode of the Grid (Asymmetric Bending/Torsion Mode)

Preliminary FEM = 24.70 HzImpact Modal Test = 22.23 HzAmbient Vib. Test = 21.72 Hz

System Identification using Ambient Vibration Data

0 500 1000 1500 2000 2500 3000-0.025

-0.015

-0.005

0.005

0.015

0.025

Time (sec)

Acc

el(g

)

0 10 20 30 40 50-10

-8

-4

0

4

8x 10-3

Time (sec)A

ccel

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 510-4

10-3

10-2

10-1

Freq (Hz)

Log

Mag

0 0.5 1 1.5 2 2.5 3 3.5 4 4.510-3

10-2

10-1

10 0

101

Frequency, (Hz)

Log

Mag

Frequency Domain Data from Pre-Processed RDs

0 0.5 1 1.5 2 2.5 3 3.5 4 4.510

-2

10-1

100

101

Frequency (Hz)

LogM

agni

tude

Modal ParametersMode Shapes: {Φ}Freq and Damping:

ω and σ

Pre-Process to Obtain Random Decrement Data

Time Domain Measurements Under Ambient Conditions

CMIF for All Data Combined, Determine Mode Shapes from

Singular Vectors

Transformation from Physical to Modal Space by Modal Filtering, Determine

Freq and Damping

Test and Analysis Method

• No=5• Random input at different locations of the

structure• Fsamp=100 Hz, no sub-sampling of the data• Random Decrement method used with 1.5Std,

N=1024 spectral lines, exponential window (1024,6,∆tx1023)

• Pseudo MIMO test set-up with Ni=5 and No=5

Vibration Response due to Random Input

0 50 100 150 200 250-0.04

-0.03

-0.02

-0.01

0

0.01

0.02

0.03

0.04

0.05Point 8

Pre-processed data using Random Decrement Technique

0 2 4 6 8 10 12-5

0

5

10x 10

-3 Point 8

Ni= pt 8, No= pt 8 (pseudo FRF)

0 5 10 15 20 25 30 35 40 45

10-2

10-1

Point 8

Ni= pt 16, No= pt 16 (pseudo FRF)

0 5 10 15 20 25 30 35 40 45 50

10-2

10-1

100

Point 16

0 5 10 15 20 25 30 35 40 4510

-3

10-2

10-1

100

101

Complex Mode Indicator Function Plot

frequency, (Hz)

LogM

ag

Mode 1 (Ambient)

0 5 10 15 20 25 30 35 40 4510

-3

10-2

10-1

100

101

eFRF Log Magnitude for Mode at 5.0218 Hz and 0.96495 zeta

Frequency

LogM

agni

tude

0 5 10 15 20 25 30 35 40 45-100

-50

0

50

100eFRF Phase

Frequency

Pha

se

0 5 10 15 20 25 30 35 40 4510

-3

10-2

10-1

100

eFRF Log Magnitude for Mode at 7.7309 Hz and 0.80509 zeta

Frequency

LogM

agni

tude

0 5 10 15 20 25 30 35 40 45-200

-100

0

100

200eFRF Phase

Frequency

Pha

se

Mode 2 (Ambient)

Mode 3 (Ambient)

0 5 10 15 20 25 30 35 40 4510

-3

10-2

10-1

100

eFRF Log Magnitude for Mode at 17.2668 Hz and 0.63745 zeta

Frequency

LogM

agni

tude

0 5 10 15 20 25 30 35 40 45-100

-50

0

50

100eFRF Phase

Frequency

Pha

se

Mode 4 (Ambient)

0 5 10 15 20 25 30 35 40 4510

-4

10-3

10-2

10-1

100

eFRF Log Magnitude for Mode at 21.7226 Hz and 0.98202 zeta

Frequency

LogM

agni

tude

0 5 10 15 20 25 30 35 40 45-150

-100

-50

0

50

100eFRF Phase

Frequency

Pha

se

Mode 5 (Ambient)

0 5 10 15 20 25 30 35 40 4510

-3

10-2

10-1

eFRF Log Magnitude for Mode at 28.27 Hz and 0.70873 zeta

Frequency

LogM

agni

tude

0 5 10 15 20 25 30 35 40 45-100

-50

0

50

100

150

200eFRF Phase

Frequency

Pha

se

Mode 6 (Ambient)

0 5 10 15 20 25 30 35 40 4510

-3

10-2

10-1

100

eFRF Log Magnitude for Mode at 34.9627 Hz and 0.6829 zeta

Frequency

LogM

agni

tude

0 5 10 15 20 25 30 35 40 45-200

-100

0

100

200eFRF Phase

Frequency

Pha

se

Mode 7 (Ambient)

0 5 10 15 20 25 30 35 40 4510

-4

10-3

10-2

10-1

eFRF Log Magnitude for Mode at 36.8232 Hz and 0.60536 zeta

Frequency

LogM

agni

tude

0 5 10 15 20 25 30 35 40 45-200

-100

0

100

200eFRF Phase

Frequency

Pha

se