The problems associated with the finite elementudanalysis of thin shell structures are discussed with theudobjective of developing a simple and efficient thinudshell finite element. It has been pointed out that theuddifficulties in the formulation of thin shell elementsudstem from the need for satisfaction of the interelementudnormal slope continuity and the rigid body displacementudcondition by the displacement trial functions. Theseuddifficulties have been surmounted by recourse to theuddiscrete Kirchhoff theory (DKT) approach and anudisoparametric representation of the shell middle surface.udA three node curved triangular element with simpleudnodal connections has been developed wherein theuddisplacement and rotation components are independentlyudinterpolated by complete cubic and quadratic polynomialsudrespectively. The rigid body displacement condition isudsatisfied by isoparametric interpolation of the shelludgeometry within an element. A convergence to the thinudshell solution is achieved by enforcement of theudKirchhoff hypothesis at a discrete number of points inudthe the element. A detailed numerical evaluation throughuda number of standard problem has been carried out.udResults of application of a patch test solution touda spherical shell demonstrates the satisfactoryudperformance of the element under limiting states ofuddeformation. It is concluded that the DKT approach inudconjunction with the isoparametric representationudresults in a simple and efficient thin shell element.
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