The concept of designing anti-slide pile is using discontinuous structure and the soil arching effect to support the sliding force. By the centrifuge model tests

studying the phenomenon of soil arching effect when anti-slide pile is used to reinforce the landslide

reproducing the soil arching in space of piles and its failure mode. Two typical failure modes are put forward; i.e. soil arching crown failure and soil arching springer failure; and the engineering measure preventing soil arching springer from failure is put forward. Based on the centrifuge model tests

using 2D particle flow method to analyse the distribution of stress and failure process of horizontal soil arching in space of piles

and then that the failure criterion of soil arching is the sharp change of load of the anti-slide piles

is proposed; i.e. the function of soil arching transfering load is lapsing partially; and this may lead to that the load of one or another pile sharply raises. The relationship of load and pile space of soil arching is also studied. The load of soil arching changes with the increasing of pile space nonlinearly. When pile space increases to a certain extent

the load of soil arching will decrease sharply; so the area of reasonable pile space can be confirmed.