“current and future bridge health monitoring systems in - samco
TRANSCRIPT
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“Current and Future Bridge Health Monitoring Systems in Hong Kong”
byEur Ing Dr. WONG, Kai-Yuen
TMCA Division, Highways DepartmentThe Government of the Hong Kong Special Administrative Region
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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Why Bridge Health Monitoring System is needed?
• Monitoring Structural Performance and Applied Loads
• Facilitating the Planning of Inspection and Maintenance
• Validating Design Assumptions and Parameters
• Updating and Revising Design Manuals and Standards
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1. WASHMS refers to Wind And Structural Health Monitoring System.
2. Application: “wind sensitivity structures”, i.e. frequencylower than 1 Hz.
3. Existing Bridges with WASHMS:(i) Tsing Ma & Kap Shui Mun Bridges - LFC-WASHMS.(ii) Ting Kau Bridge - TKB-WASHMS.
4. Future Bridges with WASHMS:(i) The Cable-Stayed Bridge (Hong Kong Side) in
Shenzhen Western Corridor - SWC-WASHMS.(ii) Stonecutters Bridge - SCB-WASHMS.
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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WASHMS
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Hong Kong IslandHong Kong IslandHong Kong IslandLantauIslandLantauLantauIslandIsland
KowloonKowloonKowloon
New TerritoriesNew TerritoriesNew Territories
Tsing YiTsingTsing YiYi
ShekouShekouShekou
ShenzhenShenzhenShenzhen
Tuen MunTuenTuen MunMun
Yuen LongYuen LongYuen Long
Sha TinShaSha TinTin
Hong Kong International Airport
Hong Kong Hong Kong International International AirportAirport
Shenzhen Western Shenzhen Western CorridorCorridor
Stonecutters Bridge
Tsing Ma Bridge
Kap Shui Mun Bridge
Ting Kau Bridge
HIGHWAYS AREA DIVISION
DEPARTMENTTSING MA CONTROL BRIDGE HEALTH
SECTION
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Tsing Ma Bridge5
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
Kap Shui Mun Bridge6
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Ting Kau Bridge 7
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Kap Shui Mun Bridge
Tsing Ma Bridge
Ting Kau Bridge
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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View of the 3 bridges from Southwest Corner of TMCA
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The two cable-stayed bridges in Shenzhen Western Corridor
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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Stonecutters BridgeHIGHWAYS DEPARTMENT
TSING MA CONTROL AREA DIVISIONBRIDGE HEALTH SECTION
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Part 2System Architecture and Operation of WASHMS
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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System Architecture of WASHMSThe four WASHMSs, i.e. LFC-WASHMS, TKB-WASHMS, SWC-WASHMS and SCB-WASHMS, are all configured into six integrating modules:
• Sensory System (SS)
• Data Acquisition and Transmission System (DATS)
• Portable Data Acquisition System (PDAS)
• Data Processing and Control System (DPCS)
• Structural Health Evaluation System (SHES)
• Portable Inspection and Maintenance System (PIMS)
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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Part 3Current WASHMS
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BRIDGE HEALTH SECTION
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Layout of Sensory System (SS)
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Layout of SS and DAS in LFC-WASHMS (TMB Part)
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Layout of SS and DAS in LFC-WASHMS (KSMB Part)
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Layout of SS and DAS in TKB-WASHMS
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BRIDGE HEALTH SECTION
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Details of Different Types of Sensory System
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Accelerometers on Main Cable of Tsing Ma Bridge
Detail of Accelerometers Accelerometers
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
Accelerometers on Main Cable
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Accelerometers
Detail of Accelerometers on Longitudinal Stabilizing Cable
Accelerometers Mounted on Longitudinal Stabilizing Cable
Bi-axial Accelerometers on Longitudinal Stabilizing Cable of Ting Kau Bridge
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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Dynamic Weigh-in-Motion Sensors
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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Traffic Direction
Dynamic Weigh-in-Motion Sensors for Lantau Fixed CrossingHIGHWAYS DEPARTMENT
TSING MA CONTROL AREA DIVISIONBRIDGE HEALTH SECTION
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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Portable Data Acquisition System (PDAS)
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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Portable Data Acquisition System for Field Vibration Measurement WorksField Measurement Works on Tsing Ma Bridge Mounting Portable Accelerometers for Suspenders
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
Battery Unit 1Battery Unit 2
Signal Conditioner (32 No. Channels)
Main Controller
Communication Unit
Remote Control Unit
UPS Unit
Isolation Transformer
PDAS and Portable Accelerometers
Accelerometers
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Data Processing and Control System (DPCS)
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
The DPCS in LFC-WASHMS & TKB-WASHMS• One UNIX-Based 64-bit Alpha Server equipped with SPIDAR
(Modified), Customized MATLAB Software and MATLAB Data Analysis Suite for overall control of SS and DAs in LFC-WASHMS
• One UNIX-Based 64-bit Alpha Server equipped with SPIDAR (Modified), Customized MATLAB Software and MATLAB Data Analysis Suite for overall control of Ss and DAS in TKB-WASHMS
• Two 32-bit SGI Intel-Based (Quad-CPU) Visual Workstations equipped GPS Monitoring Software and MATLAB Data Analysis Suite for overall control of GPS including processing, analysis, display, archiving and storage of GPS data and Video Signals from CCTV Cameras
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Structural Health Evaluation System (SHES)
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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The SHES for LFC-WASHMS & TKB-WASHMS
• One 64-bit UNIX-Based (Quad-CPU) Alpha Server equipped with MSC/NASTRAN, ANSYS/Multiphysics, ANSYS/LS-DYNA, ANSYS/FE-SAFE, Structural Dynamic-Tools and MSC/PATRAN
• One 64-bit UNIX-Based (Dual-CPU) Alpha Server equipped with Customized SPIDAR and MATLAB Data Processing Software
• One 64-bit UNIX-Based Alpha Workstation equipped with MSC/PATRAN
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BRIDGE HEALTH SECTION
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Part 4Limitations of
Current WASHMS
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BRIDGE HEALTH SECTION
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Limitations of Current WASHMS
• No Corrosion Monitoring
• Insufficient Software Facilities for Automatic Data Processing and Analysis
• No Automatic Facilities for Correlation between Measured Results and Performance Criteria given in Bridge Rating System*
• Insufficient Screens for Instant Display of Monitoring Results
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Accelerometer & Seismometer 48
Anemometer 40
Temperature Sensor 388
Temperature & Relative Humidity 28
GPS Sensor 20
Displacement Sensor 34
Strain Gauge 515
Weigh-In-Motion Sensor 12
Digital Video Cameras 16
Corrosion Cells 30
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
Stonecutters Bridge - Locations of Sensors31
Section of Tower
Section of Deck Level
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7 - Car LAR Trains
Wei
ght (
Tonn
es)
Bogie Number
Note : The measured bogie loads are derived from strain gauges installed in way-beams at Chainage 24662
Tsing Ma Bridge – Comparison between Measured and Design Bogie LoadsHIGHWAYS DEPARTMENT
TSING MA CONTROL AREA DIVISIONBRIDGE HEALTH SECTION
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Screen Display of Instantaneous Displacement of Tsing Ma Bridge: Bridge-Deck, Suspension Cables and Tower-TopsHIGHWAYS DEPARTMENT
TSING MA CONTROL AREA DIVISIONBRIDGE HEALTH SECTION
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Screen Display of Time Series Displacement of Tsing Ma Bridge : Bridge-DeckHIGHWAYS DEPARTMENT
TSING MA CONTROL AREA DIVISIONBRIDGE HEALTH SECTION
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800
850
900
950
1000
1050
1100
1150
1200
1250
1300
00:00
03:00
06:00
09:00
12:00
15:00
18:00
21:00
00:00
03:00
06:00
09:00
12:00
15:00
18:00
21:00
Time (hours)
Disp
lace
men
t (m
m)
GPS (TMB Mid Span)
4600
4650
4700
4750
4800
4850
4900
4950
5000
5050
5100
00:00
03:00
06:00
09:00
12:00
15:00
18:00
21:00
00:00
03:00
06:00
09:00
12:00
15:00
18:00
21:00
Time (hours)
Disp
lace
men
t (m
m)
Level Sensor
20
25
30
35
40
00:00:00
03:00:00
06:00:00
09:00:00
12:00:00
15:00:00
18:00:00
21:00:00
00:00:00
03:00:00
06:00:00
09:00:00
12:00:00
15:00:00
18:00:00
21:00:00
Time (hours)
Tem
pera
ture
(oC)
Air Temperature
Effective Temperature
Comparison of Vertical Deck Displacement at TMB Mid-Span by GPS and Level Sensor Measurement with Temperature Variation for two consecutive days from 03-Aug-2003 00:00
Comparison of Vertical Deck Displacement at TMB Mid-Span by GPS, Accelerometers and Level Sensor Measurement
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Tsing Ma Bridge - Deck Displacement Influence Lines by GPSHIGHWAYS DEPARTMENT
TSING MA CONTROL AREA DIVISIONBRIDGE HEALTH SECTION
A B C D
Train Effect ignored
Travel Direction of Heavy Vehicle
A
B
C
D
Deck Section
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M.W TowerCH23623 Sensor Location
T.Y TowerCH25000
Sensor LocationCH23623
+ ve µε Compression strain- ve µε Tension strainDesigned stress due to Live Load at SLS = ±60 MPa
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A1
A2
Time-series acceleration data for points A1 and A2
0 0.5 1 1.5 2 2.5 3 3.5 40
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
10.385Hz
Coherence for points A1 and A2
Auto power spectrum for points A1 and A2
0.385Hz
0.385Hz
A1A2
Deform: NORMAL_MODE, Mode 1:Freq.=0.38619: Eigenvectors, Translational
MSC. Patran 2001 r3 07-Apr-03 14:53:43
Fringe: NORMAL_MODE, Mode 1:Freq.=0.38619: Eigenvectors, Translational – (NON-LAYERED) (MAG)
Theoretical FEM for Kap Shui Mun Bridge (Theoretical frequency = 0.38619Hz)
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
Total No. of Grids = 10,914
Total No. of CBAR/ CBEAM = 24,234
Total No. of CQUAD4 = 42,906
Total No. of RBAR = 2,854
ModulusE cable = 1.95 x 1011 N/m2
E steel = 2.05 x 1011 N/m2
E concrete = 2.60 x 1010 N/m2
Mass Densityρcable = 8,200 kg/m3
ρsteel = 8,800 kg/m3
ρconcrete = 2,500 kg/m3
Total No. of Grids = 10,914
Total No. of CBAR/ CBEAM = 24,234
Total No. of CQUAD4 = 42,906
Total No. of RBAR = 2,854
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The Finite Element Model of Tsing Ma Bridge and List of Modelling Information
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HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
401st Vertical Flexural Deck and 1st Vertical Cable Mode
(Mode No. 2, Frequency = 0.11741 Hz)
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No. of nodes 2799
No. of elements 5135
Beam 3021
Quad4 2114
No. of materials 4
No. of element properties 70
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
Finite Element Model of Kap Shui Mun Bridge41
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(Mode No. 1, Frequency = 0.38619 Hz)1st Vertical Flexural Deck
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BRIDGE HEALTH SECTION
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BRIDGE HEALTH SECTION 44
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CONCLUSIONS
The WASHMS provides an effective and reliable means of bridge health evaluation which plays a key role in bridge maintenance and rehabilitation.
HIGHWAYS DEPARTMENTTSING MA CONTROL AREA DIVISION
BRIDGE HEALTH SECTION
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