## 1 Introduction
Zeolite powder promotes the generation of struvite, which also have a certain hardness and strength ([PERSON] et al., 2016). Compared with traditional concrete defect repair methods, MICP has significant advantages and broad application prospects. In the past few decades, MICP--as a new technology--has been widely discussed by scholars. Many scholars have carried out exploratory studies on the application of MICP in several fields and have achieved certain results. Figure 1: Mechanism of MICP. [PERSON] et al. [10] carried out sand stabilization and wind erosion experiments with _Sporosarcina pasteurii_, _Artemisia desertoruma_ and _Astragalus das surfagens_. Their results showed that when the concentration of consolidating fluid was 0.15 mol/L, the temperature was 20 \({}^{\circ}\)C and the concentration of bacterial fluid was OD\({}_{600}\) = 0.6, MICP improved the wind erosion resistance of desert aeolian sand by 39.83%, while the combination of desert plants improved the wind erosion resistance up to 44.08%. [PERSON] et al. [11] solidified zinc-lead composite heavy-metal-contaminated soil by combining MICP with adsorption materials. Their results showed that MICP effectively reduced the leachability of heavy metal in contaminated soil; the unconfined compression strength of the samples increased by 8.3% with the addition of 10% porous silicon, while the leaching concentration of lead decreased by 67.81% and that of zinc decreased by 63.4%. [PERSON] [12] carried out a mineralization test on the surface of stone materials using carbonate-mineralizing bacteria. The results showed that a dense mineralized film formed on the surface of sandstone and marble when using immersion and brushing methods, where the mineralized crystals were calcite and vaterite. The mineralized film was found to resist erosion caused by acid rain and showed good heat, aging, and frost resistance. The impermeability of the stone was also significantly improved. [PERSON] et al. [13] studied the use of microencapsulated bacteria for concrete self-repair. Their results showed that the repair rate of the samples with bacterial microcapsules was higher than that of the samples without bacterial microcapsules. In addition, the maximum crack width repaired by bacterial microcapsules was 970 \(\upmu\)m--almost four times that of the non-bacterial groups--while the water permeability of the bacterial groups was about 10 times lower than that of the non-bacterial groups. Concrete self-repair technologies allow concrete structures to become multifunctional and intelligent to a certain extent, it seems to be an ideal method for repairing high-temperature concrete damage. However, self-repair technologies require the mineralizing bacteria to be mixed into the concrete, the mineralizing bacteria cannot withstand high temperatures at all. That is, when repairing high-temperature concrete damage, self-repair technologies are not applicable--only passive repair technologies can be adopted. Passive repair technologies refer to the protection of surface defects and repair of cracks by artificially providing suitable conditions for MICP after concrete cracking. For existing cracks in concrete, MICP can generate a layer of CaCO\({}_{3}\) mineralized film on the surface of the concrete to block surface defects [14], and some mineralizing bacteria and repair fluid can even penetrate concrete to fill internal defects. The mechanism is shown in Figure 2.  
Figure 2: Passive repair of concrete defects by MICP [14]. [PERSON] [15] carried out an experimental study on surface filming and passive crack repair in cement mortar specimens using MICP. The results showed that cracks with a width of 0.2-0.4 mm could be repaired by the grouting method, and the flexural strength of the repaired specimens was about 200 kPa. After coating the surface of the specimens by the brushing method, the water absorption of the specimens decreased by 10%. In addition, [PERSON] also carried out a field test with MICP for controlling leakage in a basement.