Study on Improving Loess Properties with Permeable Polymer Materials

Loess has strong water sensitivity, strong collapsibility, and low strength resulting in failures such as landslides, due to its loose structure. In order to improve the loess characteristics and to better meet the needs of engineering, a colorless, transparent, and permeable composite material is proposed in this paper. Water stability, erosion, unconfined compression, and triaxial tests were conducted to investigate the change of the strength properties and soil erosion resistance. The water sensitivity and strength properties of the loess are significantly improved as the stabilizer concentration increases. When scoured for 20 min, the erosion rates of the reinforced and the unreinforced soil were 95% and 6.25%, respectively, and demonstrated a 15.12 times reduction in erosion rates. The optimal concentration of the mixed solution is 0.6%. The triaxial test, CT, and SEM scanning tests were used to reveal the intrinsic mechanisms. The results demonstrated that the internal friction angle of the reinforced soil increases from 28.09° to 30.57°, and the cohesion changes from 25 kPa to 37.4 kPa. A large number of pores with a diameter of 900–1000 μm are reduced to 0–200 μm, and some pores with a length greater than 600 μm reduce to a length of less than 200 μm; The agglomeration and cementation, the filling of pores, and the formation of membrane structures have contributed greatly to the improvement of loess properties. Furthermore, the newly composite material has significant application potential needed to stabilize soil.