Upload
vominh
View
218
Download
0
Embed Size (px)
Citation preview
Group 6
Saman Ali Akbar Sukina Hussain
Ø Density???
Ø The insufficient density Long-lasting Reduce the maintenance Reduece the rehabilitation cost
Ø Low density Oxidation Reveling Cracking Moisture damage
Ø Traditional two way mesuare density • Extract core • Unclear density gauge
Ø Researches v Non-unclear density gauge
§ Non-radioactive tool § Used electromagnetic (EM) § Inherent advantages over the nuclear density guage
§ No stringent license § Specialized storage § Extra security precautions
Ø IC } To provide continouos measurement } Large coverage } Commuri developed a neural network } The IC based on pavment stiffnes } Loading rate and stiffnes of base layer } Error measerument cause by deacrese of temperature
GPR Ø Non destructive tool Ø A functioning pavement quality control Ø Compared three candidate density prediction
Ø Rayleigh mixing
GPR Ø Several advantages
§ Collect data quicker than coring § Air-coupled GPR system
Ø GPR installation
Ø Anteena send EM waves Ø Ground-coupled antenna Ø Air-coupled antenna Ø Antenna frequency
Ø Material property for GPR Ø Permittivity Ø dielectric
} General Concept § An effective tool for QA&QC § The main challenging the
surface water effect on GPR reflect signal
} Advanced Transportation And Research Engineering Laboratory(ATREL)(University of Illinois)
§ 2 GHz air-coupled antenna § Limestone aggregate & PG
64-22 § Test temperature 63-66C § 3ft*3ft square are tested § 250 mL water § 1.7m wide drum (compactor) § Compressed air sprayer
Whole Frequency spectrum Magnification of part of the spectrum for better visualization
Figure a. Figure b.
Filtering GPR surface reflection signal
Ø Comparison of feature value plots using different feature extraction approaches
Ø Summary of test project
} GPR data collection procedure
Normalized feature value versus passing number of compactor
Ø Thickness and density measurement after construction