Consistent stiffness matrix in FE calculations of elasto-plastic bodies
In order to preserve the quadratic convergence of the Newton-Raphson method applied to elasto-plastic finite element calculations, the consistent stiffness matrix must be used. Here, the consistent stiffness matrix is derived for the generalized trapezoidal rule. Special attention is paid to the case in which the integration is performed from an elastic to an elasto-plastic state and it is shown t
