This paper presents the shell finite elements of the computer system INSANE (INteractive Structural ANalysis Environment): four-node rectangular and three-node triangular, obtained by combining membrane and bending efforts, based on the Theory of Kirchhoff; a quadrilateral of four, eight and nine nodes that combines membrane, bending and shear efforts, according to the Reissner-Mindlin Theory. After summarizing the characteristics of the elements, the paper presents results of three convergence studies and two practical applications: an arch dam and a conical-cylindrical reservoir. The results are compared with analytical solutions and those obtained with the shell finite element of SAP2000.
Structural analysis; flat shell finite elements; free software