Regulation of Calcium Source and Addition Method for MICP in Repairing High-Temperature Concrete Damage

After exposure to high temperatures, the mechanical properties and durability of concrete structures are significantly reduced, effective measures must be taken for reinforcement repair. High-temperature damage manifests as looseness, spalling, cracks, which suitable microbial-induced carbonate precipitation. When repairing high-temperature with precipitation (MICP), calcium source is an important influencing factor. The type method used add will directly affect mineralized products, in turn quality In this study, products Sporosarcina pasteurii were qualitatively analyzed appropriate addition determined. repair effect on was also verified. results showed that carbonate, mixed vaterite calcite crystals. Calcium acetate found most source, while pre-calcium-source shown optimal. At each temperature, compressive strength a certain degree recovery, water absorption exhibited reduction. 600 °C, repaired specimens increased up 202.68% compared damaged 34.32% lower than specimens. higher more obvious effect.