Abstract:

The soil mass may appear partial sliding failure under shorter clear-space circumstance, which is based on survey and analysis of cantilever piles in incised slope. Three-dimensional soil arching effect and cutting-unloading stability analysis model of soil between adjacent piles is established based on the geotechnical strength theory and analysis results about initial stress and criterion of sliding failure. An incised slope of Xiang-Yu-Ⅱ Railway project is researched based on its theoretical calculation and field engineering observation. It is indicated that trailing line on sliding curved of soil between piles is usually located just inner side of soil arching effect; the soil appears sliding trend because of tensile-shear yield failure. It is also proved by practical engineering that soil nails accepted to bracing soil mass between piles can produce preferable reinforcement benefit. The soil nails should be drilled into area of soil arching, which is based on results of numerical simulation. Wedge-compact processes from soil grains bring some anchoring effect by a certain extent to soil nails.

Key words: stability, cantilever pile, soil aching effect, unloading, soil nail