Dale P. Bentz and Symoane Mizell are members of the Building Materials Division of the NIST Building and Fire Research Laboratory. Dale Bentz's research interests include experimental studies and computer modeling of the microstructure and performance of cement-based materials. Symoane Mizell is currently an undergraduate in the Civil Engineering program at Southern University, and participated in this project as part of the SURF summer student program at NIST. Judith Devaney, Steve Satterfield, Peter Ketcham, and William George are all members of the Scientific Applications and Visualization group of the NIST Information Technology Laboratory. Judith Devaney is group leader of this research team, whose research interests include machine discovery in scientific data, scientific visualization, and parallelization of complex computational codes. William George's research interests include parallel and distributed algorithms for scientific applications and environments for these applications. Steve Satterfield's research interests include immersive visualization for scientific applications. Peter Ketcham's research interests include the visualization of both measured and simulated scientific data. James Graham and James Porterfield are members of the Information Processing Support group of the NIST Information Technology Laboratory. This group is responsible for designing, implementing, and maintaining NIST's World Wide Web presence. Daniel Quenard, Franck Vallee, and Hebert Sallee are members of the Centre Scientifique et Technique du Batiment, France. Daniel Quenard and Hebert Sallee are members of the Materials Division at the CSTB in Grenoble, France. Their research interests include heat and moisture transport in building materials and relating material microstructure to performance. Franck Vallee is a research engineer at the CSTB in Marne La Vallee, France. His research interests include the characterization of polymer-modified mortars, including their degradation during weathering. Elodie Boller and Jose Baruchel are staff members of the ID19 beamline at the European Synchrotron Radiation Facility in Grenoble, France. This beamline is used for X-ray microtomography, X-ray topography diffraction, and high resolution X-ray diffraction studies. The National Institute of Standards and Technology is an agency of the Technology Administration, U.S. Department of Commerce.