Effect of moisture on fractal dimension and specific surface of hardened cement paste by small-angle X-ray scattering

✍ Scribed by R.E. Beddoe; K. Lang

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 402 KB
• Volume: 24
• Category: Article
• ISSN: 0008-8846
• DOI: 10.1016/0008-8846(94)90184-8

✦ Synopsis

Finely divided fumed silica (Aerosil) has been used as a model substance to interpret the change in fractal dimension and specific surface of hardened cement paste (hcp) with relative humidity. Hcp is essentially a surface fractal at relative humidities below ca. 40% where the specific surface diminishes as surface area is lost around the gel particle contact points during adsorption. A "smoother" surface of lower fractal dimension results. Above ca. 40 %rh the disjoining pressure opens up the entangled hcp gel structure to produce a more mass fractal structure of higher internal surface area.