| Reactive chemical powders play an important role in the healing of concrete cracks and the improvement of mechanical properties. The corrosive environment has a significant impact on the self-healing performance of reactive chemical powder concrete. In order to obtain the optimal formula for self-healing concrete suitable for different corrosive environmental conditions, this paper conducted orthogonal experiments in three different environments based on active powder complexing agents (sodium methylsilicate and sodium gluconate in a ratio of 2:1), additives (aluminum silicate and sodium sulfate in a ratio of 1:1), calcium formate, and sodium carbonate. By testing parameters such as compressive strength, splitting strength, and strength recovery rate, the self-healing effect of concrete was evaluated, and the action of active chemical powder under different corrosion conditions was analyzed. The experimental results indicate that the erosion of corrosive ions can lead to an increase in cracks, which in turn exacerbates the cracking of concrete and affects its strength; Activated chemical powders can promote cement hydration reactions, improve the distribution of crystals inside concrete, and thus enhance self-healing ability. The composition analysis and microstructure observation show that the reactive powder reacts with calcium hydroxide and free calcium ions in the concrete to generate calcium silicate gel, ettringite crystal and calcium carbonate precipitation. These products accumulate at the crack and play a role in crack repair, strength improvement and damage repair. This study contributes to a deeper understanding of the impact of reactive chemical powders on the self-healing performance of concrete. |
