Traditionally discontinuous deformation analysis(DDA) method adopts linear displacement mode

which has many efects. To get exact stress field of the block

some improvements are developed including: directly using higher order polynomial as displacement function

sub-block division

and adopting the block-finite-element displacement mode

etc.; but these are not efficient in practice. It is suggested here to introduce meshfree interpolation mode

namely natural neighbor interpolation of natural element method

which has interpolation property

very easy to impose exactly essential boundary condition or material continuity condition; moreover it depends on no meshes and has good calculation precision as well as efficiency. Based on this mode

further analysis can be done on larger block bending or crack exploration etc to overcome defects of the linear mode as well as other modes.