Effect of Electrochemically Activated Mixing Water on Strength and Pore Structure of Fly-Ash Autoclaved Aerated Concrete


Akhmetov D. Aniskin A. Apshikur B. Baikunirova A.
February 2026Multidisciplinary Digital Publishing Institute (MDPI)

Construction Materials
2026#6Issue 1

This study assessed whether electrochemical activation of mixing water can enhance autoclaved aerated concrete (AAC), in which fly ash replaces sand as the siliceous component. Mixing water was electrolyzed in a diaphragm-type “Melesta” unit to obtain the catholyte and anolyte, and fly ash was pre-exposed to the catholyte for up to 15 min. The material’s behavior was evaluated using slurry flow tests, scanning electron microscopy, Fourier-transform infrared spectroscopy, macropore-uniformity analysis, mercury intrusion porosimetry, and shrinkage and short-term durability indicators. At an approximately constant density class near 600 kg/m3, the catholyte-pretreated fly-ash AAC mixes showed a near-monotonic increase in compressive strength with increasing fly-ash replacement (relative to the sand-based reference), while fresh-mixture fluidity decreased. The pore structure became more uniform, as indicated by a decrease in the standard deviation of pore diameters from 0.175 to 0.133 mm, and porosimetry indicated a higher micro-porosity fraction in fly-ash AAC than in sand-based AAC. Capillary shrinkage remained essentially unchanged, and short-term durability indicators (durability coefficients after 25 cycles) showed a small improvement. Overall, electrochemically activated water promoted a more regular pore system and stronger interpore walls under autoclave curing, supporting higher fly-ash utilization without loss of dimensional stability. The results are limited to one fly-ash source (Ekibastuz TPP); transferability should be verified using ashes with different glass content, fineness, and carbon/LOI.

autoclaved aerated concrete , electrochemical activation , fly ash , mercury intrusion porosimetry , pore structure

Text of the article Перейти на текст статьи

Department of Civil Engineering and Building Materials, Satbayev University, Almaty, 050000, Kazakhstan
Department of Civil Engineering and Building Materials, University North, Varazdin, 42000, Croatia
School of Earth Sciences, D. Serikbayev East-Kazakhstan Technical University, Ust-Kamenogorsk, 070000, Kazakhstan
Department of Architecture and Construction, Korkyt Ata Kyzylorda University, Kyzylorda, 120000, Kazakhstan

Department of Civil Engineering and Building Materials
Department of Civil Engineering and Building Materials
School of Earth Sciences
Department of Architecture and Construction

10 лет помогаем публиковать статьи Международный издатель

Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026