# Program for finite element analysis of grillages with circumferential arc-shaped and straight elements

## Palavras-chave:

Grillages, circumferential arcs, Finite Element Method, program## Resumo

This paper presents the development of a program for structural linear-elastic analysis of grillages with

circumferential arc-shaped elements and regular straight bars under concentrated and distributed loads. It was

based on the Finite Element Method, and the code was written in FORTRAN (FORmula TRANslation). The force

method was used initially to calculate the flexibility matrix and then by inversion the stiffness matrix and load

vectors were determined. Results of deflections, rotations, bending, torsion and shear, from numerous examples

were checked against some of those available in the scientific literature, in order to validate the code. A comparison

was also made with the validation results and those calculated by the virtual work method, or extracted from two

similar softwares where the curved bars needed to be approximated by various small straight elements. The

program developed was shown to give closer values to the exact solution, with a much simpler input data (just

angles and radiuses), than the other softwares.