Abstract:In order to reveal the influencing factors of the stability of cement-improved loess subgrade, the variation laws of different cement dosages, compaction coefficients, water-stability coefficients of modified loess, dry-wet residual strength ratio, and freeze-thaw residual strength ratio at different ages were studied. The results show that: the cement dosage is ≥4%, the growth curve of the water stability coefficient of the improved loess is gentle, and the improvement of water stability is small; the compaction coefficient is increased from 0.92 to 1.00, and the water stability coefficient is increased by 21.6% to 25.6% at 90 days, and the water stability The water stability coefficient increased significantly faster in the first 14 days than in the later stage. The health-care period was extended from 14 days to 90 days, and the water stability coefficient increased by approximately 7.4%. The compressive strength of the improved loess under dry, wet, and freeze-thaw conditions increased linearly with the increase of the cement dose or the compaction coefficient. As the number of cycles increased, the compressive strength of the modified loess gradually decreased. The compressive strength tends to a stable value, and the residual strength ratio of 15 times of wet and dry is about 44%; after the number of wet and dry cycles ≥ 12 times, the compressive strength of the improved loess gradually decreases to a stable value at a cement dosage ≥ 3%, and freezes The average residual strength ratio after melting 12 times was 42%.