Physical–Mechanical and Microstructural Properties of Non-Autoclaved Aerated Concrete with Ash-and-Slag Additives

Non-autoclaved aerated concrete (NAAC) is gaining attention for its strength-to-weight ratio and sustainability benefits. Produced by incorporating a blowing agent into a binder, aggregate, and water mixture, NAAC offers a lightweight and porous construction material. Ash and slag waste (ASW), primarily composed of silicon, aluminum, iron, and calcium oxides, presents significant potential as a sustainable additive. However, industrial-scale processing of ASW still needs to be explored in Kazakhstan. This study evaluates the feasibility of utilizing ASW from the Ust-Kamenogorsk Thermal Power Plant to produce earthquake-resistant NAAC. Incorporating 31.5% ASW by weight optimizes compressive strength, achieving 2.35 MPa and significantly improving the mechanical properties. Chemical and microstructural analyses confirm ASW’s suitability as a construction material. The study also introduces innovative processing methods and explores convolutional neural network models for predicting material structure changes, providing insights into optimizing production processes. The findings address the research objectives by confirming the viability of ASW in NAAC production and demonstrating its potential for sustainable construction. The results offer a pathway for industrial-scale applications, contributing to waste utilization and resource conservation.