Field Testing and Modelling of the Italian Smart Runway

Instrumentations

Silvia PortasImad L. Al-Qadi

Mauro ConiHao Wang

Jongeun Baek

UNIVERSITA DEGLI STUDI DI CAGLIARIDipartimento Ingegneria del TerritorioSOGAER

Italian civil aviation authorityItalian civil aviation authority

Ente Nazionale per l’aviazione civileEnte Nazionale per l’aviazione civile

Outline

Introduction Objective and Scope Site Description and Instruments Responses from Instrumentation Preliminary Results from Modeling Summary

Introduction A reconstructed runway was instrumented to

measure: Stresses Strains Temperature profile Moisture content

Monitoring parameters affecting pavement behavior Airplane traffic intensity Loading maneuver Airplane speed Environmental conditions

Objective and Scope Analyze runway pavement response under

various loading conditions: Pressure profile

Strain response

Predict runway pavement performance: Pavement response measurements

Pavement structure modeling

Better runway pavement response understanding

Instrumented Site Cagliari’s Airport main runway Location

close to runway Head between Aiming Point and TDZ

Pavement Cross Section

Selected Instruments Strain and deformation measurements:

H-type strain gauges for HMA

Specially-modified LVDTs for unbound materials

Pressure measurements

Hydraulic pressure cells Environmental condition measurements:

T-type thermocouples; TDRs

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HMA Strain Measurements

45 H-type strain gauges to measure strains at the bottom of HMA layers 9 Longitudinal 9 Transversal

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Deformation Measurements

36 LVDTs to measure deformation in granular layers Macro Sensors LVDTs GHSER 750-1000 Macro Sensors LVDTs GHSE 750-1000

Vertical Pressure Measurements

Hydraulic pressure cells to measure vertical stresses under pavement layers 9 on each layer

Temperature and Moisture Measurements

In-house built T-type thermocouples to measure temperature profile

Time Domain Reflectometry to measure moisture content of granular layers Campbell Scientific 2-probe CS 616-L Calibration using in-situ materials

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Instrument Response

Instrument responses to two loading types were measured: Impulse loading: Falling Weight Deflectometer Moving load: truck at four various speeds

Pressure Cell Response

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Data Collection Method

Real traffic data

Triggering system

Collection frequency

Collection duration

Traffic Monitoring

Airport traffic data

Video camera

Current Traffic & Expected Measurements

Typical Airplanes Boeing 737-800

MD-82

Airbus 320

Heaviest Airplane

Antonov- Multileg Landing Gear

Response measured

Stress and strain response to main gear

Typical Loading Conditions

Take-off and Landing Speed over sensors: 30–190 km/h Average aircraft weight: 63-74 tons

Typical Responses

Boeing 737-800 - Landing 100 km/h

Typical Responses

MD-82 - 31 km/h

3-D Finite Element Modeling

3-D FE model is used to capture

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Infinite element

Loading area

Non-uniform contact pressure

Moving tire load

Implicit dynamic analysis

Viscoelastic HMA layer

Infinite boundaries

Calculated vs Measured Pressure for Truck Loading at

10 km/h

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0.1 0.2 0.3 0.4 0.5Time (s)

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Measurement

Calculation

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0.1 0.2 0.3 0.4 0.5Time (s)

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Measurement

CalculationUniform Tire Pressure

Non-Uniform Tire Pressure

Calculated vs Measured Pressure for B737 Loading at

190km/h

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0.00 0.02 0.04 0.06 0.08Time (s)

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th (k

Pa) Measurement

Calculation

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0.00 0.02 0.04 0.06 0.08Time (s)

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pth

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Measurement

CalculationUniform Tire Pressure

Non-Uniform Tire Pressure

Summary

Cagliari airport runway pavement was instrumented with 149 sensors

New instrument installation techniques were successfully implemented and data was collected from:• LVDT’s• HMA strain gauges• Pressure cells • Thermocouples

Pavement response data was compared to FEM analysis results

Summary

Calculated pressure is lower than measured values near-surface. The difference becomes smaller with depth Non-uniform contact pressure needs to be

considered in further analysis

Future Research

Continue analyzing data under various loading conditions

Calculate pavement responses under realistic tire-pavement contact stresses and compare results to field measurements

Thank YouQuestions?