Phase-Resolved Strain Measurements in Hydrated Ordinary Portland Cement Using Synchrotron X-rays
Abstract:X-ray diffraction methods developed for the determination of residual stress states in crystalline materials have been applied to study residual strains and strains because of mechanical loading of ordinary portland cement paste. Synchrotron X-rays were used to make in situ measurements of interplanar spacings in the calcium hydroxide (CH) phase of hydrated neat portland cement under uniaxial compression. The results indicate that strains on the order of 1/100 000 can be resolved providing an essentially new technique by which to measure the phase-resolved meso-scale mechanical behavior of cement under different loading conditions. Evaluation of these strain data in view of published elastic parameters for CH suggests that the CH carries a large fraction of the applied stress and that plastic interactions with the matrix are notable.
Document Type: Research Article
Affiliations: 1: Department of Chemical Engineering, Tennessee Technological University, Cookeville, Tennessee 38505-5013 2: Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6064 3: Materials Processing Center, University of Tennessee, Knoxville, Tennessee 37996
Publication date: 2006-09-01