Characterization and Modeling of Pores and Surfaces in Cement Paste

• DOI: 10.3151/jact.6.5
• Publication Date: 2008-03-18T05:51:10Z
• Authors: Hamlin M. Jennings; Jeffrey W. Bullard; Jeffrey J. Thomas; Jose E. Andrade; Jeffrey J. Chen; George W. Scherer
• Keywords: Calcium silicate hydrate; Nanometre; Shrinkage; Characterization; Specific surface area; Saturation (graph theory)

Cement-based materials have complex multi-component, multiscale structures that first form through chemical reaction and then continue to change with time. As most classes of materials, the porosity cement paste strongly influences its properties, including strength, shrinkage, creep, permeability diffusion. Pores in range size from nanometers millimeters, numerous investigations models been reported literature. This paper reviews some key concepts related our understanding pore system surface area. A major reason for complexity cement-based is principal product, calcium silicate hydrate (C-S-H), forms a significant volume fraction internal, nanometer-scale pores. gel contains water also adsorbed solid surfaces, blurring distinction between phase The changes not only composition extent reaction, but relative humidity, temperature, applied load. can be characterized by their area, size, fraction, saturation, connectivity, precise quantitative are still available. useful approach characterizing structure document influence time external factors on structural changes. Scientific progress will facilitated development accurately describe use predict properties. particularly important because chemistry commercial concretes changing more rapidly than laboratory experimentation long-term properties such as durability. Some possible discussed.