Stress recovery and error estimation for shell structures

The Penalized Discrete Least-Squares (PDLS) stress recovery (smoothing) tec hnique developed for two-dimensional linear elliptic problems [1-3] is adap ted here to three-dimensional shelf structures. The surfaces are restricted to those which have a 2-D parametric representation, or which can be built -up of such surfaces. The proposed strategy involves mapping the finite ele ment results to the 2-D parametric space which describes the geometry, and smoothing is carried out in the parametric space using the PDLS-based Smoot hing Element Analysis (SEA). Numerical results for two well-known shell pro blems are presented to illustrate the performance of SEA/PDLS for these pro blems. The recovered stresses are used in the Zienkiewicz-Zhu a posteriori error estimator. The estimated errors are used to demonstrate the performan ce of SEA-recovered stresses in automated adaptive mesh refinement of shell structures. The numerical results are encouraging. Further testing involvi ng more complex, practical structures is necessary. Copyright (C) 2000 John Wiley & Sons, Ltd.