CONFIDENTIAL PRIVATE INFORMATION 9/13/2018 Application of ground penetrating radar (GPR) in pavement investigation Istvan Sereg Geophysics Technician URS Infrastructure & Environment UK Limited Meeting of Young Geoscientists - Tatabanya, Hungary March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION Contents 9/13/2018 Introduction Reasons & Goals GPR-Survey methodology Sitework High-Speed GPR Survey vs. Slow-Speed GPR Survey Office work Processing steps Advantages & Limitations Additional tests NDT tests DT tests Results References Application of Ground Penetrating Radar in pavement investigation 2 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION 9/13/2018 Introduction 3

CONFIDENTIAL PRIVATE INFORMATION Introduction 9/13/2018 GPR basics Permittivity – Velocity of wave propagation Conductivity - Attenuation Application of Ground Penetrating Radar in pavement investigation 4 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION Introduction 9/13/2018 Reasons Maintanence work due to pavement failure Cracking: reflective cracks, alligator cracks, thermal cracks, block cracks, linear craks, edge cracks, slippage; Distortion: rutting, shoving or corrugations; Disintegration: raveling/weathering, delamination, potholes; Surface defects: bleeding or flushed asphalt, polished aggregate Upgrading Goals Provide information to engineers undertaking pavement rehabilitation projects, such as: Structure information Layer thickness Location of changes of construction Presence of moisture Application of Ground Penetrating Radar in pavement investigation 5 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION Introduction 9/13/2018 NSWP - Near Side Wheel Path OSWP - Off-Side Wheel Path Application of Ground Penetrating Radar in pavement investigation 6 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION 9/13/2018 GPR-Survey methodology 7

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 Sitework Planning and optimising geophysical investigation. Performing sitework. OSWP NSWP Application of Ground Penetrating Radar in pavement investigation 8 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 High-Speed GPR Survey Slow-Speed GPR Survey Advantages Fast datacollection Possible progression with the trafficflow Disadvantages Poor lateral resolution Only air-lunched antennae can be used Used for taking longitudinal profiles. Advantages Ground-coupled antennae can be used Good lateral resolution Disadvantages TM cooperation needed due to avoiding H&S issues Prohibited trafficflow Slow datacollection Used for taking longitudinal and/or transverse profiles. Application of Ground Penetrating Radar in pavement investigation 9

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 Office work Data relocation! (referencing to marker posts, HAPMS, site chainage) Data processing Core calibration Interpretation (thickness plots, apparent moisture plots) Reporting RAW DATA PROCESSED DATA Application of Ground Penetrating Radar in pavement investigation 10 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 Cores Application of Ground Penetrating Radar in pavement investigation 11 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION Advantages & Limitations 9/13/2018 Antennae freqency Velocity [mns-1] Max. penetration c. [m] Wavelength [m] Min. detectable object (resolution) 900 MHz 0.1 mns-1 1 m 0.11 m 0.035 m – 0.055 m 1 GHz (air coupl.) 0.6 m 0.1 m 0.03 m – 0.05 m 1.5 Ghz 0.5 m 0.07 m 0.025 m – 0.045 m 90-95% Accurancy up to: Application of Ground Penetrating Radar in pavement investigation 12 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 High-speed example – recent activity Application of Ground Penetrating Radar in pavement investigation 13 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 Slow-speed example Application of Ground Penetrating Radar in pavement investigation 14 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 High-speed example Raw GPR data Processed GPR data Application of Ground Penetrating Radar in pavement investigation 15 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 High-speed example Picked GPR data Interpreted thickness plot Application of Ground Penetrating Radar in pavement investigation 16 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION GPR-Survey methodology 9/13/2018 Slow-speed example Application of Ground Penetrating Radar in pavement investigation 17 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION 9/13/2018 Additional tests 18

CONFIDENTIAL PRIVATE INFORMATION Additional tests 9/13/2018 NDT FWD Visual evaluation DT Coring Laboratory tests Application of Ground Penetrating Radar in pavement investigation 19 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION 9/13/2018 Results 20

CONFIDENTIAL PRIVATE INFORMATION Results of the GPR survey 9/13/2018 High-speed example Raw GPR data Interpreted plot Application of Ground Penetrating Radar in pavement investigation 21 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION Results 9/13/2018 Complex and detailed information (Final report) about the road structure Material thickness profile Apparent moisture content Mechanical properties (stiffness, compression strength) Pavement life Application of Ground Penetrating Radar in pavement investigation 22 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION 9/13/2018 References 23

CONFIDENTIAL PRIVATE INFORMATION References 9/13/2018 C. Blades, E. Kearney: Asphalt Paving Principles, CLRP#04-3, March, 2004 W. Muller: Application of ground penetrating radar to road pavement rehabilitation, Queenslands Roads Edition No 7, 7 March, 2009 L. Liu: GPR for fast pavement assessment, JHR 07-310, May, 2007 I. Sereg: Application of ground penetrating radar (GPR) in characterization of concrete and building structures, Meeting of Young Geoscientists – 25th-26th March, 2011. Győr, Hungary Application of Ground Penetrating Radar in pavement investigation 24 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012

CONFIDENTIAL PRIVATE INFORMATION Thank you for your attention! istvan.sereg@urs.com 9/13/2018 Thank you for your attention! Application of Ground Penetrating Radar in pavement investigation 25 Meeting of Youndg Geoscientists – Tatabanya, Hungary – March 30-31, 2012