A SEISMIC DESIGN METHOD FOR CANTILEVER-TYPE STABILIZING PILES IN SOIL SLOPE

Permanent displacement and plastic zone in the stable strata of a soil slope occur generally in the slope reinforced by stabilizing piles under the condition of intensive seismic action. However, the two important factors are usually omitted in the traditional aseismic design and analysis for slopes with cantilever-type stabilizing piles. Based on the principle of the rigid Newmark sliding model and limit analysis, the computational method is proposed that engineered landslide thrust on a stabilizing pile can be determined, by taking into consideration design safety factor and permanent displacement of the slope with piles. Meanwhile, according to the condition that some area in the stable strata of the slope is in the plastic state, the section of a stabilizing pile in the stable strata can be further divided into the segment in plastic zone of the strata and the segment in elastic zone of the strata. Therefore, the former can be regarded as cantilever beam model with uniformly lateral limit ground reaction; the latter can be analyzed by use of elastic foundation beam model. Their continuous conditions including internal forces and deformation of a pile and lateral ground reaction should be met at the interface between the two segments. The proposed method is demonstrated by a soil slope engineering example, in which calculation procedure and corresponding results are given in detail by the three section analysis method for the aseismic design of a cantilever-type stabilizing pile. The results show further that the proposed method is reasonable and cost effective.