传统的非连续变形分析法(DDA)采用线性位移模式存在诸多缺陷。为准确计算块体应力场,传统上一般直接增加位移函数的多项式阶次,或进行子块体划分或耦合有限元等改进措施,但应用上仍不够方便有效。建议引进无网格节点位移插值模式,采用自然单元法中的自然邻接点插值(NNI)法,具有插值特性,易于准确实施边界条件或材料连续性条件,且具有无网格特征和良好的计算精度,计算更快效。可在此基础上进一步分析大块体弯曲、裂纹扩展破坏形式等,以解决线性位移模式等的不足。
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.