skip to main content

SciTech ConnectSciTech Connect

Title: Observing the setting and hardening of cementitious materials by X-ray dark-field radiography

Novel X-ray imaging methods expand conventional attenuation-based X-ray radiography by the phase- and the dark-field contrasts. While weakly absorbing structures in the specimen can be better visualized in phase contrast, the dark-field contrast provides information about morphological sub-pixel microstructures. Here we report an application of dark-field X-ray radiography for imaging the time-resolved setting process in fresh cement. Our results demonstrate that the microstructural changes within the cement result in a decreasing dark-field signal. We quantify this imaging signal with a time-dependent dark-field scatter coefficient and show its good correlation with the compressional wave velocity. We further present images based on a pixel-wise analysis of the scattering signal and a corresponding logistic fit. These images emphasize the benefit of dark-field imaging of cementitious materials as it provides two dimensional spatial information on the processes within the sample while other established testing techniques only provide information on the bulk average.
Authors:
 [1] ;  [1] ;  [2] ;  [2] ;  [1]
  1. Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany)
  2. Lehrstuhl für Zerstörungsfreie Prüfung, Centrum Baustoffe und Materialprufung, Technische Universität München, 81245 München (Germany)
Publication Date:
OSTI Identifier:
22475515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Cement and Concrete Research; Journal Volume: 74; Other Information: Copyright (c) 2015 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; CORRELATIONS; HARDENING; HYDRATION; MICROSTRUCTURE; SMALL ANGLE SCATTERING; TIME DEPENDENCE; TIME RESOLUTION; TWO-DIMENSIONAL SYSTEMS; WAVE PROPAGATION; X-RAY DIFFRACTION; X-RAY RADIOGRAPHY