In this paper, a Total Lagrangian formulation based on the Logarithmic strains is developed. The variation in these strains is based on the variation of the Engineering strains and the variation of Green strains. The "true" Cauchy stresses thus obtained are compared with the Engineering stresses based on the Engineering strains obtained from a Total Lagrangian formulation. The Cauchy stresses obtained based on the assumption of small Engineering shear strains are also compared with the above

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... tioned stresses. A Geometric nonlinear Total Lagrangian formulation applied on two-dimensional elasticity using 4-node plane finite elements was used. The formulation was implemented into the finite element program (NUSAP). The solution of nonlinear equations was obtained by the Newton-Raphson method. The program was applied to obtain stresses for three numerical examples. The evaluation of the accuracy of the formulation was based on comparing the stresses obtained with those from the other two formulations as stated above. The paper concludes that all three Total Lagrangian formulations converge to the correct solution, as expected, for small strains. For moderate and large strains, there is a clear difference between the Cauchy and the Engineering stresses. The formulation based on the Logarithmic strains results in the accurate evaluation of the "true" Cauchy stresses. These stresses can be used in the geometric and material nonlinear analyses of large deformation problems using constitutive equations based on Logarithmic strains.