Numerical and Experimental Investigation of an Elliptical Paraboloid Shell Model
For practical engineering purpose, a new flat shell element baptized (ACM_Q4SBE1) is presented in this paper. The formulated element can be used for the analysis of thin shell structures; no matter how the geometrical shape might be. Tests on standard problems have been examined. Since, the analysis of thin shell structures has generally been purely carried out on a theoretical basis; it is of importance to present some experimental results of an elliptical paraboloid under uniformly distributed load pressure. The results obtained from both numerical and experimental work are presented. Index Terms— Elliptical Paraboloid, finite element, flat shell element.
A Comparative Study between Displacement and Strain Based Formulated Finite Elements Applied to the Analysis of Thin Shell Structures
: The analysis and design of thin shell structures is a topic of interest in a variety of engineering applications. In structural mechanics problems the analyst seeks to determine the distribution of stresses throughout the structure to be designed. It is also necessary to calculate the displacements of certain points of the structure to ensure that specified allowable values are not exceeded. In this paper a comparative study between displacement and strain based finite elements applied to the analysis of some thin shell structures is presented. The results obtained from some examples show the efficiency and the performance of the strain based approach compared to the well known displacement formulation.
Three-dimensional anisotropic and inhomogeneous elastic media matrix analysis for small and large displacements
SummaryA matrix displacement technique for analysing three-dimensional anisotropic and inhomogeneous elastic media is given for small and large displacements. The body is idealized by an assembly of finite tetrahedra. Using the novel device of ‘natural’ stresses, loads and elemental stiffness, concise expressions for stiffness of the complete system are set up. Hence small displacement solution is obtained. Extension to large displacements proceeds via an incremental technique and an additional geometrical stiffness simulating effects of change of geometry on equilibrium conditions. It is proved that geometrical stiffness of tetrahedron derives from equivalent six-bar framework. Joint presence of loads and thermal actions is included.