THE ANALYSIS OF STRUCTURE DEFORMATION USING DDA WITH THIRD ORDER DISPLACEMENT FUNCTION

摘要

Third order displacement function is introduced into DDA (DDA3O), which can easy to analysis the nonlinear distribution of deformation, stress and strain within a single block. In this paper, additional nodes were inserted on the boundary. So, when large deformation is involved, even the original straightly boundary of block will deform to one formed by curved edges, the simplex integration along the curved edge can increase accuracy and simulation of contact between blocks can be more reasonable. On the other hand, the problem of transferring the initial stress from previous step to next step is difficulty and unresolved problem, because of the strain matrix of high order displacement function involving the unknown variables x, y. A new method presented herein is inherent previous the displacement of block to next step, which is proved right and efficient. At last, some example was calculated to demonstrate the excellent accuracy and efficiency of DDA3O.