저감적분 연속체 유한요소 해석에 의한 탄소성 굽힘문제에서의 응력계산Stress Evaluation in Elasto-plastic Bending Problems by Continuum Finite Element Analysis with Reduced lntegration
This paper demonstrates evaluation of stress components in elasto-plastic bending problems for each increment step with a finite element method using a four-node continuum quadrilateral element. Inaccurate evaluation of stress components is caused by conventional integration schemes such as a full integration scheme (FI), a directional reduced integration scheme (DRI) and a selective reduced integration schem (SRI), which can be corrected by a reduced integration scheme (RI) with hourglass control. A finite element program with reduced integration schemes is applied to the elasto-plastic bending problem of a cantilever beam. The numerical result demonstrates oscillating behavior of stress and deviation of stress values calculated by a FI, DRI or SRI scheme from that by a RI scheme. The application also studies the effect of the number of finite element layers in the thickness direction on the accuracy and convergence of calculated solutions.