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Title: Measurement of aggregate interfacial porosity in complex, multi-phase aggregate concrete: Binary mask production using backscattered electron, and energy dispersive X-ray images

Abstract

This paper presents for the first time a method for the accurate segmentation of complex (multi-phase) natural aggregate particles, from greyscale backscattered electron images (BEI) of hardened concrete, so that interfacial porosity may be measured. Energy dispersive X-ray (EDX) spectra are collected from phases present in aggregate particles to identify the most abundant and therefore useful elements to be captured during later mapping. Appropriately captured energy dispersive X-ray dot maps are used to progressively construct a multi-phase composite aggregate binary mask, for aggregate particles composed of more than one mineral. The mask image is then re-processed in combination with the backscattered image, to produce an accurate hardened cement paste (HCP) porosity mask, which is used to measure the distribution of interfacial porosity around aggregate particles.

Authors:
 [1];  [2]
  1. Department of Civil and Environmental Engineering, Imperial College London Imperial College Road, London, SW7 2BU (United Kingdom). E-mail: m.head@imperial.ac.uk
  2. Department of Civil and Environmental Engineering, Imperial College London Imperial College Road, London, SW7 2BU (United Kingdom)
Publication Date:
OSTI Identifier:
20793273
Resource Type:
Journal Article
Resource Relation:
Journal Name: Cement and Concrete Research; Journal Volume: 36; Journal Issue: 2; Other Information: DOI: 10.1016/j.cemconres.2005.09.007; PII: S0008-8846(05)00223-1; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CEMENTS; CONCRETES; IMAGES; PARTICLES; POROSITY; SCANNING ELECTRON MICROSCOPY; X RADIATION

Citation Formats

Head, Martin K., and Buenfeld, Nick R. Measurement of aggregate interfacial porosity in complex, multi-phase aggregate concrete: Binary mask production using backscattered electron, and energy dispersive X-ray images. United States: N. p., 2006. Web. doi:10.1016/J.CEMCONRES.2005.0.
Head, Martin K., & Buenfeld, Nick R. Measurement of aggregate interfacial porosity in complex, multi-phase aggregate concrete: Binary mask production using backscattered electron, and energy dispersive X-ray images. United States. doi:10.1016/J.CEMCONRES.2005.0.
Head, Martin K., and Buenfeld, Nick R. Wed . "Measurement of aggregate interfacial porosity in complex, multi-phase aggregate concrete: Binary mask production using backscattered electron, and energy dispersive X-ray images". United States. doi:10.1016/J.CEMCONRES.2005.0.
@article{osti_20793273,
title = {Measurement of aggregate interfacial porosity in complex, multi-phase aggregate concrete: Binary mask production using backscattered electron, and energy dispersive X-ray images},
author = {Head, Martin K. and Buenfeld, Nick R.},
abstractNote = {This paper presents for the first time a method for the accurate segmentation of complex (multi-phase) natural aggregate particles, from greyscale backscattered electron images (BEI) of hardened concrete, so that interfacial porosity may be measured. Energy dispersive X-ray (EDX) spectra are collected from phases present in aggregate particles to identify the most abundant and therefore useful elements to be captured during later mapping. Appropriately captured energy dispersive X-ray dot maps are used to progressively construct a multi-phase composite aggregate binary mask, for aggregate particles composed of more than one mineral. The mask image is then re-processed in combination with the backscattered image, to produce an accurate hardened cement paste (HCP) porosity mask, which is used to measure the distribution of interfacial porosity around aggregate particles.},
doi = {10.1016/J.CEMCONRES.2005.0},
journal = {Cement and Concrete Research},
number = 2,
volume = 36,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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