The author would like to thank Northeast Solite Corporation* and W.R. Grace & Co. - Conn. for supplying the fine lightweight aggregates and chemical admixtures used in this study, respectively, Mr. Max Peltz (BFRL/NIST) for assistance with preparing the mortar mixtures, and Mr. Kenneth Snyder (BFRL/NIST) and Mr. Thomas Holm of the Expanded Shale, Clay, and Slate Institute for their thorough reviews of the manuscript.
*Certain commercial products are identified in this paper to specify the materials used. In no case does such identification imply endorsement by the National Institute of Standards and Technology, nor does it indicate that the products are necessarily the best available for the purpose.