Abstract: Study on the landslide prevention and control is one of the hot topics in geological hazards currently. The passive soil arching effect, adjacent to the piles, is an important factor influencing the horizontal load-bearing capacity of anti-slide piles. Regrettably, the investigation into the impact of passive soil arching effect on the internal force and deformation of anti-slide piles shaft remains somewhat limited. In response, building upon the existing strain wedge methodology, this study analyzed the passive soil arching effect and its mechanical characteristics along the embedded segment of anti-slide piles. Subsequently, an improved strain wedge calculation model for the row piles is proposed, effectively incorporating the passive soil arching effect in front of the anti-slide piles. Verification attests to the accuracy of this proposed model. The significant accomplishments of this research are as follows: with the introduction of the concept and the stress characteristic of passive soil arching ahead of the anti-slide piles, the judgment condition for the soil failure in front of anti-slide piles was proposed as the failure of the passive soil arching. Correcting the calculation width of the strain wedge front edge for pile group to 1 times the pile spacing, can make the passive soil arching stress analysis of row piles more reasonable. Considering the impact of static lateral soil pressure on the soil mass and pile-soil interaction in front of the anti-slide piles, can make the stress status calculation of passive soil arching more reasonable, furthermore, can make the calculation of internal forces and deformation of anti-slide piles shaft more rational. The improved strain wedge model for row piles proposed in this paper can more accurately reflect the variations law of soil resistance in front or anti-slide piles during the interaction between adjacent piles, and the developed iterative computation program for optimizing the internal force and deformation of row piles shaft can serve as a novel option for practical engineering computations.

Key words: anti-slide piles, passive soil arching, improved strain wedge, horizontal load-bearing capacity, loess