Click here to access/download;Manuscript;Advances in Pantographic Structures.pdf Click here to view linked References Francesco dell'Isola et al.

SUMMARYPhase-field approaches to fracture offer new perspectives toward the numerical solution of crack propagation. In this paper, a phase-field method for finite deformations and general nonlinear material models is introduced using a novel multiplicative split of the principal stretches to account for the different behavior of fracture in tension and compression. An energy-momentum consistent integrator is developed and applied to the arising nonlinear coupled phase-field model. This approach is thermodynamically consistent in the sense that the first law of thermodynamics if fulfilled with respect to the dissipation function. The capabilities and the performance of the proposed approach is demonstrated in several representative examples.

SUMMARYAn energy-momentum consistent integrator for non-linear thermoelastodynamics is newly developed and extended to domain decomposition problems. The energy-momentum scheme is based on the first law of thermodynamics for strongly coupled, non-linear thermoelastic problems. In contrast to staggered algorithms, a monolithic approach, which solves the mechanical as well as the thermal part simultaneously, is introduced. The approach is thermodynamically consistent in the sense that the first law of thermodynamics is fulfilled. Furthermore, a domain decomposition method for the thermoelastic system is developed based on previous developments in the context of the mortar method. The excellent performance of the new approach is illustrated in representative numerical examples.

No abstract

In the present work, a new director-based finite element formulation for geometrically exact beams is proposed. The new beam finite element exhibits drastically improved numerical performance when compared with the previously developed director-based formulations. This improvement is accomplished by adjusting the underlying variational beam formulation to the specific features of the director interpolation. In particular, the present approach does not rely on the assumption of an orthonormal director frame. The excellent performance of the new approach is illustrated with representative numerical examples. CopyrightIn this section, we treat the theory of the geometrically exact beam, also known as the special Cosserat beam, introduced by [2] and [1]. The theory is developed by restricting the kinematics of the three-dimensional continuum to a beam-like kinematic. By inserting the reduced kinematics DIRECTOR-BASED BEAM FINITE ELEMENTS IN SKEW COORDINATES 115with the surface element d 2  D d 1 d 2 . For the sake of clarity, the contributions due to external forces and inertia are developed in compact form in the Appendix.