Soft intercalated slope stability optimization with a modified polymer curing agent

Abstract

The demand for high-grade roads is significantly higher in developing countries. However, slopes containing coal gangue weak interlayer pose significant safety risks to highways, railways, and other infrastructures. To address this issue, this study aims to find the best polymer cement ratio scheme of traditional pure acrylic emulsion polymer curing agents. Based on this scheme, a reinforcement method was designed, which combined modified polyvinyl acetate with the coal gangue soft interlayer. The slope test results using a rigid model box showed that the shear strength of the root–soil composite in the PVAC group was higher than that in the pure acrylic emulsion group under different vertical consolidation pressures. Over time, the cumulative soil loss rate of the pure acrylic emulsion group gradually increased, and the soil pH decreased. Conversely, the PVAC group showed minimal changes in these two indicators with time. Under the same conditions, the slope shear strength of the PVAC group remained stronger than that of the pure acrylic emulsion group. The standard deviations of multiple tests for the PVAC group and pure acrylic emulsion group, under a vertical consolidation pressure of 100 kPa, were 7.2 kPa and 9.2 kPa, respectively, indicating greater stability in the PVAC group. With a stability coefficient of 3.39, which surpasses that of the pure acrylic emulsion group, the PVAC group exhibited enhanced slope stability. These results indicate that this method can effectively enhance the stability of coal gangue soft interlayer slopes without causing environmental pollution.