Prebored hole is an effective construction measure for reducing the squeezing effect of sinking-pile. For the problem of soil squeezing by sinking-pile adjacent to slope

it is assumed that the soil is the linear elastic constitutive model

The process of sinking-pile is simulated by a series of continuous spherical cavity expansion

Based on the mirror image method and present literatures

the soil squeezing displacement expression caused by pile sinking adjacent to slope is deduced which considers the influence of prebored hole. The results show that the soil compacting effects which far away from the hypotenuse free boundary side are not as obvious as the opposite side due to the influence of asymmetrical displacement boundary; the compacting effects become more obvious with the steeper of the hypotenuse free boundary; the influence of inclination boundary to the soil squeezing displacement would be gradually smaller with the increase of free inclination boundary angle; the aperture and hole-depth are important factors for the compacting effects of pile sinking adjacent to slope; combination of the aperture and hole-depth can effectively reduce the compacting effects. The results provide some reference value for engineering design.