non destructive testing & modal analysis for seismic … · non destructive testing & modal...

Non Destructive Testing &

Modal Analysis for Seismic

Risk Assessment

INTERFEROMETRIC RADAR & MODAL ANALYSIS

SONIC TEST

1

ARIEL A. DEVAL

UNIVERSITY OF TEXAS AT ARLINGTON

PROJECT OBJECTIVES

TO PERFORM A FINITE ELEMENT ANALYSIS OF THE

STRUCTURES IN ORDER TO MATCH THE SPECTRAL RESPONSE

IN DYNAMIC ANALYSIS.

TO OBTAIN THEORETICAL BACKGROUND ON MODAL ANALYSIS,

RADAR INTERFEROMETRY AND ON SITE STRUCTURE CASE

STUDIES

INTRODUCTION

2

PROJECT TITLE

AIDICO

RESEARCH

MENTOR

AIDICO

LABORATORY HAZARD TYPE

Non-destructive testing and

modal analysis for seismic risk

assessment.

José Vicente

Fuente Monitoring Earthquake

SONIC TEST Accelerometer MEMS, Instrumented Impact Hammer,

Datalogger IMC Cronos SL-8 for 16 channels

BACKGROUND & EQUIPMENT

3

SONIC TEST


4

PROCEDURE:

1. SET UP LUGGAGE AND PROGRAM

2. CONNECT MEMS TO LUGGAGE IN CORRECT ORDER

3. ARRANGE MEMS LINEARLY ACROSS THE WIDTH OF THE PILLAR

4. TAKE DISTANCES OF HEIGHT OF PILLAR, WIDTH, AND DEPTH.

5. USE IMPACT HAMMER TO STRIKE THE PILLAR IN A POSITION

BETWEEN THE MEMS

6. REPEAT STRIKE WITH IMPACT HAMMER BETWEEN FIRST AND

SECOND MEMS AND LAST 2 MEMS.

7. REARRANGE MEMS ON LESS THICK (CENTER) OF THE PILLAR

AND REPEAT PROCEDURE.

8. ANALYZE RAW DATA

BACKGROUND: SONIC TEST BASICS

SONIC TEST

A type of NON-DESTRUCTIVE testing.

Pulse waves are transmitted through a material, in this case

reinfoced concrete, to detect internal characteristics and

properties of a structure.

f = capp/2d SONIC TEST OBJECTIVES

• To identify the frequencies in

order to compare various

results from different testing

methods.

• To model the structure under

a non-controlled environment.

BACKGROUND: SONIC TEST BASICS

EXPERIMENTAL RESULTS

SONIC TEST 1 & 2

17.86 17.88 17.9 17.92 17.94 17.96-250

-200

-150

-100

-50

0

50

100

150

200

250

Time (seconds)

Sig

nal W

avefo

rm

A-Scans of Impact on Sonic Test 01

Hammer

SISM02

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 100000

5

10

15

20

25

X: 1224

Y: 19.5

X: 1865

Y: 20.61

X: 2523

Y: 11.23

X: 2032

Y: 12.95

Frequencies (Hz)

FF

T (

random

valu

es)

Spectral Response (FFT) of Sonic Test 01 - SISM02

X: 233.1

Y: 3.464

5.66 5.68 5.7 5.72 5.74 5.76 5.78-1200

-1000

-800

-600

-400

-200

0

200

400

600

800

Time of Flight (seconds)

A-Scans of Impact on Sonic Test 02

HAMMER

SISM02

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 100000

5

10

15

20

25

30

X: 2029

Y: 28.81

X: 1230

Y: 16.28

Frequencies (Hz)

FF

T (

random

valu

es)


SAMPLE CALCULATION

Depth=0.96 m

From MIRA:

Cp= 3976 m/s

Cs= 2385 m/s

Use equation

F= Capp/(2*d)

Theoretical Frequencies

F=3976/(2*0.96)=2.07 kHz

F=2385/(2*0.96)=1.24 kHz

Experimental Frequencies

FFT Graphs F=1.23 Hz

Capp=2*d*F=

Cs=2*0.96*1230=2361 m/s

Cp=2*0.96*2029=3895 m/s


SONIC TEST 4 & 5

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 100000

5

10

15

20

25

30

35X: 1182

Y: 32.6

X: 2456

Y: 28.44

Frequencies (Hz)

FF

T (

random

valu

es)


SAMPLE CALCULATION

Depth=0.70 m

From MIRA:

Cp= 3976 m/s

Cs= 2385 m/s

Use equation

F= Capp/(2*d)

Theoretical Frequencies

F=3976/(2*0.70)=2.84 kHz

F=2385/(2*0.70)=1.70 kHz

Experimental Frequencies

FFT Graphs F=1.28 Hz

Capp=2*d*F=

Cp=2*0.70*2431=3403 m/s

Cs=2*0.70*1282=1795 m/s


POISSON’S RATIO

Sample Results:

Cs=2*0.96*1230=2361 m/s (lateral)

Cp=2*0.96*2029=3895 m/s (longitudinal)

Cs=2*0.70*1282=1795 m/s (lateral)

Cp=2*0.70*2431=3403 m/s(longitudinal)

Sonic Test 2 ratio = Cs/Cp = 2361/3895 = 0.60 ν=(1-(2*0.6^2))/(2-(2*0.6^2)) = 0.21 *Correct Measurement with

sensors in thicker section of pillar.

Sonic Test 5 ratio = Cs/Cp = 1795/3403 = 0.31 ν=(1-(2*0.31^2))/(2-(2*0.31^2)) = 0.45 * Not correct measurement.

Interferometric Radar

IBIS-FS Image by Interferometric Survey


10

INFEROMETRIC RADAR TEST

OBJECTIVES

To evaluate and compare the

results of the interferometric

radar with those of the sonic

test.

To use the FFT of the

measurement points to

determine frequencies and

displacements of the

structure at those points.

RADAR BASICS

RADAR: RADIO DETECTION AND RANGING

The radar is able to detect the presence of the

object/structure and is able to measure the distance between

the aparatus and the object, R.

Antenna used in this project, G=23 dB

12

TEST OBJECTIVES

INFEROMETRIC RADAR TEST OBJECTIVES

To evaluate and compare the results of the

interferometric radar with those of the sonic test.

To use the FFT of the measurement points to

determine frequencies and displacements of the

structure at those points.

RADAR EQUIPMENT

PROCEDURE:

1 . ARRANGE THE RADAR AT A DISTANCE

WHERE IT WILL DETECT A

REFLECTING POINT OF THE

STRUCTURE.

2 . SET UP THE GEOMETRY SETT INGS IN

THE PC. (D ISTANCE, ANGLES, HEIGHT)

3 . BEGIN RUNNING IBIS FS AND AIM THE

RADAR AT THE REFLECTION POINT.

4 . START THE PROJECT FROM THE PC TO

SELECT RANGE BINS.

5 . ONCE THE RANGE BINS DESIRED ARE

SELECTED, BEGIN TO COLLECT

DISPLACEMENTS AND FREQUENCIES.

6. TAKE ABOUT 45 MINS OF DATA .

7 . PROCESS RAW DATA .

RADAR EQUIPMENT

IBIS RADAR

Bridge loads: Concrete self-weight = 2500

kg/m3

Steel self-weight = 7850

kg/m3

AIDICO BRIDGE EXPERIMENT

15

16

BRIDGE EXPERIMENT RESULTS

0 0.5 1 1.5 2 2.5 30

0.02

0.04

0.06

0.08

0.1

0.12

0.14

X: 1.26

Y: 0.1098

X: 1.44

Y: 0.1289

X: 2.16

Y: 0.08462

Frequency [Hz]

Pro

jecte

d D

ispla

cem

ent

[mm

/Hz]

2014.07.16-09.47.58-dynS-000001-SurvSpectrum

Bridge Conf 1

Reflector 6.4 m

X: 2.94

Y: 0.07576

Rbin 14

0 0.5 1 1.5 2 2.5 30

0.05

0.1

0.15

0.2

0.25

0.3

0.35

Frequency [Hz]

Pro

jecte

d D

ispla

cem

ent

[mm

/Hz]

2014.07.16-09.47.58-dynS-000001-SurvSpectrum Bridge Conf 1 Reflector 8.9 m

X: 1.26

Y: 0.3502

Rbin 19

0 0.5 1 1.5 2 2.5 30

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

X: 1.26

Y: 0.5064

X: 1.44

Y: 0.1183

frequency [Hz]

Pro

jecte

d D

ispla

cem

ent

[mm

/Hz]

2014.07.16-11.02.29-dynS-000000-SurvSpectrum

Bridge Conf 2

Reflector 6.4 m

Rbin 14

Reoccuring Frequency 1.26 Hz

17

BRIDGE EXPERIMENT RESULTS

0 0.5 1 1.5 2 2.5 30

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

X: 1.44

Y: 0.4617

X: 1.26

Y: 0.784

Frequency [Hz]

Pro

jecte

d D

ispla

cem

ent

[mm

/Hz]


Rbin 17

0 0.5 1 1.5 2 2.5 30

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

X: 1.26

Y: 0.8207

Frequency [Hz]

Lin

e o

f S

ight

Dis

pla

cem

ent

[mm

/Hz]


X: 1.44

Y: 0.08116

Rbin 13

Reoccuring Frequency 1.26 Hz

18

CONCLUSIONS

THE RADAR TEST RESULTS MATCHED THE THEORETICAL AND

EXPERIMENTAL RESULTS OF THE SONIC TEST.

THE REOCCURING FREQUENCY FOR THE RADAR TEST WAS 1.26 Hz

WHICH MATCHED 1.28 HZ FROM THE SONIC TEST.

CASE STUDY: ANCIENT CHIMNEY

INDUSTRIAL BRICK CHIMNEY IN AGOST, SPAIN (NEAR ALICANTE)

PROBLEM: FATIGUE BY WIND CAN CAUSE THE CRACK PATTERN APPEARENCE.

THE CRACK PATTERN AFFECTS TO THE STRUCTURAL CONDITION.

THE STRUCTURAL CONDITION CAN BE ASSESSED BY STRUCTURAL HEALTH MONITORING.

HAZARD: CRACKS COULD CAUSE THE CHIMNEY TO COLLAPSE

IT IS POSSIBLE TO ASSESS THE STRUCTURAL CONDITION BY DYNAMIC MODAL TEST USING NONCONTACT TECHNOLOGY AS RADAR.


¨The University of Alicante begins the

rehabilitation of one of the two

ancient clay industrial structures

still standing. The objective of the

project is to avoid a collapse and

reinforce it with glass fibers for a

seismic event (earthquake).¨ -Jose

Antonio Rico of L’Alacanti in Agost

• Archeological Industrial

Monuments

• Corrosion and Wind factors

CHIMNEY EXPERIMENTAL RESULTS

INTERFEROMETRIC RADAR – D ISPLACEMENT AND FREQUENCIES FOR DIFFERENT BINS

PERPENDICULAR TO THE OPENING

TARGET 18.4 m

Displacement ±1.0 mm

Frequencies **1.38 Hz

TARGET 19.4 m

Displacement ±1.2

mm




PERPENDICULAR TO THE OPENING

TARGET 20.9 m



TARGET 26.9 m

Displacement ±1.0

mm




PARALLEL TO THE OPENING

TARGET 13.0 m



TARGET 16.4 m

Displacement ±0.6

mm





TARGET 19.4 m



TARGET 22.9 m






TARGET 26.9 m



NUMERICAL MODEL FOR CHIMNEY

COMSOL MULTIPHYSICS PROGRAM

• Boundary conditions: Footing & Wind Load

• Wind load: although this is actually a dynamic load for our

purpose it was modeled as a static load in order to determine

immediate displacement it would cause.

• Used two types of solvers:

• Eigenfrequencies & Time Dependent

• Varying material properties

• As with many ancient structures, the real properties are unknown

so it was useful to solve the problem with different properties

• Elastic Modulus, E

• Rigidity

• Poisson’s ratio

• Damping parameters

NUMERICAL MODEL FOR CHIMNEY

Solver: Linear Parametric

Static Load on X-faces: 1400 N/m2

IT CAN BE SHOWN, THE X-

DISPLACEMENT ON THE LOAD

FACE IS AROUND 25 MM.

THIS RESULT MATCHES WITH

EXPERIMENTAL DATA

Solver: EigenFrequency


Frequency 1 (flexural on X) = 1.52 Hz



Frequency 2 (flexural on Y) = 1.52 Hz



Frequency 3 (torsinal 1) = 8.71 Hz



Frequency 4 (torsinal 2) = 8.72 Hz



Frequency 5 (dilating) = 15.2 Hz



Frequency 6 (hybrid tors.&flex) = 20.5 Hz

ORTHOTROPIC BRICK MASONRY

MATERIAL SIMULATION

Modeling with

dif ferent elastic

constants, it is

possible to get the

experimental

dif ferent main

frequencies in the

top of the chimney.

COMPARISON MODEL vs TESTS

Solver: Linear Parametric


IT CAN BE SHOWN, THE X-

DISPLACEMENT ON THE

LOADED FACE IS AROUND 25

MM.

THIS RESULT MATCHES WITH

EXPERIMENTAL DATA

CONCLUSIONS

Non-destructive technology supplies accurate

experimental data to numerical simulations.

Numerical simulation allow the explanation of different

results from NDT tests to explain different behaviors

depending on material properties.

Non-destructive technology allows diagnosis of structural

soundness of structures.

In this way, future damage, possible collapsing, and

hazardous situations can be prevented.

ACKNOWLEDGMENTS

THANK YOU MENTOR, JOSEVI!

THANKS AIDICO & STAFF!

THANKS DR. YAZADANI, UTA, & NSF!

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