Effect of oversize grain on soil arching of anti-slide piles

Colluvial landslide materials are mainly loose deposits which content of gravelly soils, which are difficult to get mechanics parameters by soil test. Colluvial landslides are distributed in the wold widely, especially in China. In order to make the slopes stable, many treatment projects have put into practice. Anti-slide pile project is one of the most important treatment methods. But the work mechanism of the anti-slide piles in the colluvial is still unclear, then lead to the design of the anti-slide piles project is not effectively. The work mechanism of the anti-slide piles and the soil arching effect is studied by FEM. The result shows that the influence of the size and distribution of oversize grain is significant. To ensure the soil arching effect of the anti-side piles work efficiently, the distribution of oversize grains around the piles should be considered.