Abstract
This is the first reporting in Materials Science and Engineering at UNSW of accurate quantitative digital micro-structural analyses of 95-100mm
diameter concrete cores utilising 64-bit image acquisition, and 64-bit image analysis software.
The results of these newly developed, highly accurate automated quantitative analysis techniques to forensically compare micro-structural
variations between hardened concrete core samples are presented.
Quantitative micro-structural digital analysis of large image data files (>3 GB), have only recently been able to be studied outside the proprietary
concrete laboratories with the release of 64-bit Image J, 64-bit Windows 7 operating system and 64-bit Office 2010.
This thesis will demonstrate that only three simple procedures need to be followed to attain accurate quantitative digital analysis of large hardened
concrete micro-structures:
1. The samples must be prepared by slow and careful fine diamond lapping with surface cooling to prevent any underlying damage to
concrete micro-structure from overheating, thus preventing pull-outs of fine aggregate and sand particles within the fine cement paste
matrix. This also ensures that accurately sized sharp pore perimeters remain and very fine air voids and hairline shrinkage micro-cracks
are revealed.
2. The digital image needs to be obtained by a highly accurate white cold cathode fluorescent lamp IR LED light sourced digital scanner,
such as a flat bed Epson Perfection V700 Photo scanner with true optical resolution of at least 6400ppi x 6400ppi (~4μ2). It will be
preferable in the near future to use a much higher resolution, as for example 50800ppi x 50800ppi (0.5μ2), comparable to the best
current proprietary photo scanners and saved in uncompressed TIFF file in 128-bit software, as soon as 128-bit Windows 8 becomes
available.
3. All digital image files must not be altered or enhanced in any way. Any enhancement of the digital image file changes forever its
ability to be used for accurate quantitative digital analysis. All image analysis software calculations thereafter can only be then roughly
qualitative.
Hundreds of digital image files ranging from 72ppi to 6400ppi in 32-bit and 64-bit digital analysis software were required to be able to say that the
calibrated, guaranteed, and highly accurate quantitative analyses of complex microstructures from a variety of hardened concrete mixes were
correct.
The 64-bit Image Analysis and Processing Software enabled me to develop automated, highly accurate, forensic comparative methods to study
the macro-structures and micro-structures of commercial sized concrete core samples.