In this paper, it will combine with a masonry pagoda project, carried out numerical simulation analysis of mechanism to the key factors, it include the depth, diameter, distance of the hole, main conclusion is as follows:(1) The hole depth decided the area of the weaken layer. The hole depth should be slightly exceed the projection of tower gravity center.(2)the hole diameter has the key effect to control the rectification rate. The change of hole distance could influence weaken foundation, the distance also has a great influence to effective section. The parameter of diameter and distance should be take Comprehensive consideration. It is unnecessary to use too large hole diameter and put the adjacent hole too close.(3) The plastic zone between adjacent holes can accelerate the stress of soil redistribute ，aggravated plastic deformation.