FINITE ELEMENT ANALYSIS USING SHELL ELEMENTS ON RETICULATED STRUCTURES

Abstract

This paper studies the possibility of using SHELL elements on structures that are usually designed using BEAM or BAR elements. Using SHELL elements in such structures, named reticulated structures, opens the possibility to remove material from the structures’ members by adding holes. Once the members get holes, the final weight of the structure and material consumption will drop. In order to develop the study, a total of three different structures were analyzed using the software ANSYS^®. This software uses the Finite Element Method to solve the equations originated from the designed structure upon it is meshed and the boundary conditions are set. Several results between SHELL and SOLID elements for each one of the structures were compared. The comparison of SHELL model with a SOLID model is used as a verification process, for SOLID elements are known to return accurate values. All of the meshes were tested by the independence mesh study to check its convergence. It is shown that the results are in a very good acceptable range with differences no bigger than 0.1 mm for displacements, and the map of von Mises stresses are pretty similar. Von Mises stresses for Finite Element Analysis for the C-Shaped Truss are shown in a figure comparing the results between the two finite elements used. This figure shows that there are no major differences between the SHELL and SOLID analyses. The Finite Element Analyses results were compared to analytical solutions, also. In this case, a noticeable difference in one structure for von Mises Stress was found. This difference, however, is understandable and reasonable, given the works presented on this paper.