Critical slope stability with double row pile reinforcement under 2D and 3D FEM modeling

This study aimed to determine the contribution of double rows pile reinforcement on slope stability to minimize the impact of landslides. The study constructed the sandy soil slope with Rc 88% and slope angle 50° scaled models on the box 1.0x1.0x1.5 m. The aluminum hollow piles were used for reinforcement, while the first-row pile diameter is 3.2 cm, and the second-row pile has varied diameters (3.2, 2.5, 2.0, 1.5 cm). The slope was gradually loaded by 40 kg until it began to fail. After determining the critical bearing capacity from a physical laboratory test, the Factor of Safety (FS) was the slope with two rows of pile reinforcement for all variations in diameter might enhance the FS compared to a slope with one-row pile reinforcement and an unreinforced slope. The pile diameter that provided the optimum FS was the most prominent (3.2 cm). The 2D FEM analysis showed the model increased the FS to 8.672% and 31.655% on the 3D FEM analysis. The slopes with double rows piles may enhance the slope bearing capacity to 197.801%. The test results show that toe-type failure occurs on slopes.