Abstract:
The water sensitivity of loess is an important factor affecting the protection and restoration of earthen sites in loess areas. The site dominated by loess caves in the northern Shaanxi revolutionary site was caused by the water sensitivity of the loess, leading to the surface of the cavern to fall off, chalk and seepage. When the modified glutinous rice mortar is used to cure loess as a wall repair material, the study of micro-mechanism scoping to improve water sensitivity will become an important aspect. Absorption rate is an important index to evaluate the change of the composition of the substance inside the cured loess caused by the change of the pore structure. With the changing in water absorption rate of cured soil through different gum-fixing ratios, the microscopic action mechanism of the modified glutinous rice mortar solidified loess is analyzed by XRD and SEM. The results show that the saturated water absorption of the solidified soil with a cementation ratio of 0.45 decreases to 18.71% after 28 days of curing, and the XRD analysis also indicates that the content of calcite in the solidified soil with 0.45 cementation ratio is increased most obviously. In the microscopic image, the gypsum and calcite crystals in the modified glutinous rice mortar fill the pores, which change the original pore structure and enhance the adhesion between the soil particles. The curing effect of modified rice mortar changes the original pore structure, material composition of the loess and improves its water sensitivity. The application of the loess to the repair of the loess kiln wall surface will reduce the wall surface disease caused by water sensitivity.