In this study, unconfined compressive strength, calcium carbonate content, scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) tests were conducted to study the influence of cementation solution concentration, urease concentration, enzyme gel ratio, organic material type and content on the curing effect of enzyme-induced carbonate precipitation (EICP) combined with organic materials. The results show that the organic material type has the most prominent influence, with skim milk powder demonstrating the best combined curing effect. The unconfined compressive strength and calcium carbonate content increase with the increase of urease concentration and organic material content, whereas they initially increase and then decline as the cementation solution concentration and enzyme gel ratio increase. The optimal combination of curing parameters obtained herein is a cementation solution concentration of 1.35 mol/L, a urease concentration of 100 g/L, an enzyme gel ratio of 1∶1, and a skim milk powder content of 3%. After incorporating skim milk powder, larger and massive calcium carbonate crystals are deposited between the particles of solidified desert sand, and smaller and spherical calcium carbonate crystals are deposited on the particle surfaces, effectively filling the intergranular pores while significantly reducing the number of large-sized pores and improving the pore structure. The findings of this study are expected to contribute to desertification control and infrastructure construction in desert areas.
Cui et al. (2026) studied this question.