[15] presented the formulation and flexural properties of thin fly ash geopolymers and found that the flexural performance of thin geopolymers exhibited comparatively similar flexural strengths but a higher strength/thickness ratio compared to geopolymers with thickness greater than 40 mm. [PERSON] [16] conducted research on effects of different admixtures on the properties of fly-ash-based geopolymer composites. Many scholars have conducted extensive research on the preparation of geopolymers in which the main raw materials include fly ash, metakaolin, silica fume and slag. Research on the reaction products, strength and microstructure of materials is relatively detailed, mainly focusing on the reaction mechanism, structural properties and applications of geopolymers. Due to their high early strength, good durability, volume stability and high interfacial bonding strength, geopolymers are also suitable for road repair and reinforcement. [PERSON] et al. [17] prepared road alkali-activated blast furnace slag (AABFS) paste which could be applied effectively in road-grouting reinforcement. Using Fullerfine sand powders (Fuller-FS) as a fine inorganic admixture, [PERSON] et al. [18] conducted research on effects of this addition on rheological properties, drying shrinkage and mechanical strength of MGGMs. [PERSON] et al. [19] developed a new kind of powder geopolymer groutingmaterial (S-F powder Geopolymer) and investigated the properties. [PERSON] et al. [20] investigated the workability, mechanical properties and microstructure of geopolymer grouting material (GGM) containing high-calcium basalt fiber (HCBF). [PERSON] et al. [21] developed a high-performance geopolymer grouting material based on slag and fly ash and investigated the properties. [PERSON] et al. [22] prepared geopolymer road grouting pastes in different mixture ratios of volcanic ash (VA) and metakaolin (MK). [PERSON] et al. [23] experimentally investigated the effects of varying contents of Na\({}_{2}\)O in a modified sodium silicate, sodium silicate moduli (M-s), and the contents of granulated blast furnace slag (GBFS) on the compressive strength and drying shrinkage of fly-ash (FA)-based geopolymer grouting materials at different ages. [PERSON] et al. [24] conducted an experimental investigation on the performance variation of geopolymer grouting material with varied mass fractions of raw materials and presented the optimal mix proportion. [PERSON] et al. [25] prepared slag/fly-ash-based geopolymer materials for cement-stabilized macadam in road bases. [PERSON] et al. [26] explored the effects of FAG on road base layer properties using a mechanistic laboratory evaluation and its practicability in pavement base layers. [PERSON] et al. [27] proposed a fly-ash-/slag-based geopolymer as an alternative to cement for stabilizing soft soils. [PERSON] et al. [28] conducted research on the mechanical properties of fly ash-slag-based geopolymer to solve various problems, such as difficulty to store and transport liquid activator of the existing geopolymer grouting materials. In summary, some researchers focused on the preparation of geopolymers the main raw materials of which included fly ash, metakaolin, silica fume, and slag. Some studies also focused on the mechanical properties of geopolymers using them as grouting materials for conventional road maintenance methods. To the best of our knowledge, little work had been reported to address the mechanical properties and microscopic morphology of geopolymer which is used as a grouting material in homogenized micro-crack crushing technology. In this study, a slag-based geopolymer grouting material was prepared, which was used in concrete pavement rehabilitation after homogenized micro-crack crushing. Through indoor tests, the compressive strength, flexural strength, flexural bonding strength, and compressive shear bonding strength under different ratios of water to slag powder of geopolymer were studied.