JAS3D v. 2.4

JAS3D is a three-dimensional finite element program originally designed to solve Lagrangian quasistatic non-linear mechanics problems, and subsequently extended to include both implicit and explicit dynamics. A set of continuum equations describes the nonlinear mechanics involving large rotation and strain. Innovative multilevel nonlinear iterative methods are used to solve the equations. A wide variety of material constitutive models are available, and contact interface logic is implemented. Two Lagrangian uniform-strain elements are available: an eighth-node hexahedron for solids and a four-node quadrilateral for shells. Both use hourglass stiffness to control zero-energy modes. In addition, a version of the hexahedron is available with uniform pressure and a deviatoric response scalable from the mean response of the original element up to a fully-integrated response. Bodies under analysis may be loaded by surface pressures and concentrated forces, specified displacements, or body forces from gravity, steady-state transport, or thermal expansion.