Stabilizing a post-landslide loess slope with anti-slide piles in Yan’an, China

• Published in: Environmental earth sciences 2021-11, Vol.80 (22), p.739-739, Article 739
• Main Authors: Li, Hao, Du, Qin-wen
• Format: Article
• Language: English
• Subjects: Bedrock; Biogeosciences; Boreholes; China; cost effectiveness; Cross-sections; Deformation; Drilling; Earth and Environmental Science; Earth pressure; Earth science; Earth Sciences; Environmental Science and Engineering; friction; Geochemistry; Geology; Highway construction; Hydrology/Water Resources; Landslides; Loess; Mathematical models; Monitoring; Numerical models; Optimization; Original Article; Piles; safety factor; Safety factors; Slope stability; Slopes; Soil; Soil investigations; Soils; Stabilizing; Surveys; Terrestrial Pollution; Three dimensional models
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-021-10051-8

Anti-slide piles are economical and effective slope-retaining structures that are widely used in highway subgrade protection, and the mechanism of these piles has been attracting increasing attention. In this study, a cutting loess slope in Shaanxi Province, China, was excavated during the construction of a highway, and a row of anti-slide piles was used in the field to stabilize the slope. The results of in situ surveys and drilling indicated that a landslide had previously occurred. To ensure the safety of the slope, detailed monitoring measures were applied. Soil boreholes and pile monitoring holes were drilled to investigate the horizontal displacement. The pile length was 40 m with a cross section of 2 m × 3 m and a pile spacing of 6 m. To explore the interaction between high slopes and long anti-slide piles, a three-dimensional numerical model was established. Thereafter, the stress and deformation characteristics of a single pile were studied, and factors such as the pile length, embedment ratio, pile spacing, and cross section were considered. A comparison of the simulation and measurement results demonstrated that increasing the pile length may cause a shallow landslide, leading to a lower safety factor of the slope. It was found that s  = 4 b can be thought of as the most cost-effective arrangement and the soil arching effect in the vertical direction of 8–20 m is stronger; the earth pressure behind the pile will decrease due to the friction between the bedrock and soil near the sliding surface. It was also found that rectangular piles are more suitable for stabilizing high slopes. This study provides optimization choices for the slope and has reference value in the application of stabilizing piles.