Abstract: Based on field prototype tests, the anti-sliding performance of single pile with steel-tube grouted for multiple times is studied. The steel-tube is analyzed in aspects of landslide thrust, soil pressure and bending moment of pile body, and the grouting effect and failure mode. The test results show that the root shaped anti-sliding bodies composited by cement column are formed by multiple sectional control grouting technology. This structure can effectively improve the shear strength of the soil around the pile, and enhance the anti-sliding performance of the steel-tube single pile structure effectively. Compared with the conventional steel pipe, the horizontal anti-sliding force of single pile is increased by 35 kN, and the horizontal bearing capacity is increased by about 50.72% compared with the conventional steel-tube, and better prevents landslide. The bending failure of the steel-tube occurs under the action of landslide thrust, and the maximum bending moment appears near the slip surface. It is suggested that the reinforcement ratio of the piles near the sliding surface should be properly enhanced to improve the anti-sliding ability.

Key words: steel-tube, splitting grouting, anti-sliding mechanism, model test