The Use of Acid-Resistant Alkali-Activated Cement (AAC) Concrete скачать в хорошем качестве

The Use of Acid-Resistant Alkali-Activated Cement (AAC) Concrete

Presented By: Wil Srubar Affiliation: University of Colorado Boulder Description: Microbial-induced concrete corrosion (MICC) is a major durability challenge of ordinary portland cement (OPC) concrete exposed to biogenic sulfuric acid in sewer infrastructure applications. Acid-resistant alkali-activated cement (AAC) concrete has been identified as a potential solution to this pervasive infrastructure durability challenge. Previous research has demonstrated that the acid resistance of AACs is dependent on a number of physical and chemical factors, including acid type, concentration, activity, and chemical composition of AACs. This presentation will highlight current mechanistic understanding of the acid resistance of AACs in the context of published and ongoing work on the sulfuric acid resistance of slag- and metakaolin-based AACs without and with mineral admixtures. Mechanisms are explained using data from experimental investigations of acid resistance involving electron microprobe analysis and X-ray diffraction after semi-dynamic leaching in sulfuric acid solutions. Microstructural differences in AACs after acid exposure were correlated with changes in bulk permeable porosity and corrosion depth. The presentation will provide evidence for a more complex AAC acid degradation mechanism than previously observed and add insight for the development of AAC concrete materials with exceptional acid resistance.