Abstract
An alkali-activated cement (AAC) based on natural SiO 2-containing materials - grounded porcellanite (Pr) and highly dispersed pure quartz sand - was examined. Sodium hydroxide was used as an alkali activator. The pressed specimens were prepared and were cured in an autoclave at a pressure of 1.6 MPa and a temperature of 205 °C. It was shown that the strength of cement as well as compound and the microstructure of its hydration products depend on the cement composition. It was distinguished that autoclave-cured cementing matter comprises secondary quartz and the mass of sodium hydrated silicates along with the initial Pr crystal phases. After a 2-year storage under water, 15% Na2SO4, and Dead Sea water, the strength of specimens decreased by 17.5-20%. Control specimens, prepared with Portland cement and immersed in a 15% Na2SO 4 solution for 2 weeks, were broken up completely. Positive results of long-term durable tests suggest that an AAC based on natural raw material would be stable in other salt solutions.
Original language | English |
---|---|
Pages (from-to) | 1417-1422 |
Number of pages | 6 |
Journal | Cement and Concrete Research |
Volume | 33 |
Issue number | 9 |
DOIs | |
State | Published - 1 Sep 2003 |
Keywords
- Alkali-activated cement
- Durability
- Hydration product
- Mechanical properties
ASJC Scopus subject areas
- Building and Construction
- Materials Science (all)