Consolidation Efficacy of Nano-Barium Hydroxide on Neogene Sandstone

This study focuses on the sandstone of the Kizil Grottoes as the research object. Sandstone samples reinforced with barium hydroxide nanoparticle (Ba(OH)2) solutions at different concentrations were subjected to mass and deformation monitoring, wave velocity tests, triaxial shear tests, and conventional mercury intrusion porosimetry (MIP) to investigate the reinforcement mechanism and effectiveness of nano-Ba(OH)2 on Kizil sandstone. The results indicate that after treatment with nano-Ba(OH)2, the strength and wave velocity of the sandstone samples significantly increased, with the 15% concentration showing the optimal reinforcement effect. Nano-Ba(OH)2 enhances the cementation between sandstone particles, alters pore morphology and size distribution, reduces capillary water rise height, and inhibits sulfate ion crystallization and recrystallization, thereby achieving the dual effects of strength reinforcement and deterioration prevention.