A calculation method for thrust on the fore piles of double-row stabilizing piles used to reinforce landslides

In order to better understand the thrust and its distribution pattern on the fore piles of double-row full-length piles and embedded rear-row piles combined with full-length fore-row ones used to reinforce landslides, an inclined slice method is provided in this article. The slide mass between the two pile-rows is divided into many oblique slices parallel to the local slip surface. These slices are involved in four basic types at various depths. Calculation formula of the thrust of each inclined slice on the loading segment of the fore pile can be derived based on the static equilibrium principle, and the distribution pattern of the thrust and its resultant force can be determined. The analysis results of the examples indicate that the thrust on the fore pile determined by the proposed method shows approximately parabolic distribution and its peak point is close to the slip surface. The calculated thrust on the fore piles under the embedded rear-row piles are 8.6% to 10.6% smaller than that under the full-length rear-row piles. The proposed thrusts are about 10.6% to 13.4% higher than those by the classical transfer coefficient method, and are relatively close to the numerical results via FLAC^3D.