Authors: Cedric Lequesne, A. Plumier, H. Degee, Anne Marie Habraken
Abstract: The fatigue behaviour of the welded beam-to-column connections of steel moment
resisting frame in seismic area must be evaluated. The cohesive zone model is an efficient solution
to study such connections by finite elements. It respects the energetic conservation and avoids
numerical issues. A three-dimensional cohesive zone model element has been implemented in the
home made finite element code Lagamine [1]. It is coupled with the fatigue continuum damage
model of Lemaître and Chaboche [2]. The cohesive parameters are identified by the inverse method
applied on a three points bending test modelling.
847
Abstract: This paper presents a computational framework for simulation of delamination that combines the features of the discontinuous Galerkin methods with the versatility of the cohesive zone models. Within the finite element formulation of the discontinuous Galerkin methods, displacement discontinuities (jumps) are allowed across the element boundaries. Thus, the cracks are naturally included in the model without modifying the initial mesh. The displacement discontinuities across the element boundaries are used to compute the separations in the cohesive fracture law. The delamination initiation occurs when the traction across the element boundaries reaches its maximum; when the separation exceeds a critical value, total decohesion occurs. Numerical example is presented to illustrate the validity and effectiveness of the present methodology.
501
Authors: Vladislav Kozák, Zdeněk Chlup
Abstract: Ceramic matrix composites reinforced by unidirectional long ceramic fibre are very perspective materials. The only disadvantage of such materials is relatively high brittleness at room temperature. The main micromechanism acting as toughening mechanism is the pull out. There are other mechanisms as crack bridging, crack deflection etc. but the primer mechanism is mentioned pull out which is governed by interface between fibre and matrix. The contribution shows a way how to predict and/or optimise behaviour of composite by application of cohesive zone method using the FEM numerical package Abaqus. The presented results from numerical calculations are compared with experimental data.
231
Authors: Jin Chang Wang, Lei Zhang, Jia Min Zhang
Abstract: The research methods of Cohesive Zone Model (CZM) are introduced and the parameters of cohesive zone model in ABAQUS software are calibrated based on the cohesive constitutive model determined by the fracture energy. Besides adopting exponential cohesive zone model, this paper applies a bilinear one to simulate the crack propagation of a simply supported single-edge notched concrete beams SE(B) (Mode I) and make comparisons with experimental result. Finally, the results represent effectiveness of the effective modulus and the special advantage in term of failure of fracture based on the cohesive zone model, which is of directly guiding significance for achieving a deep going understanding of crack propagation.
1503
Authors: Ai Min Jiang, Gao Chun Li, Ai Ping Tian
Abstract: In order to analyze failure phenomena and mechanical properties of propellant-liner interface material, both experimental study and modeling were carried out. The adhesive system was observed under tensile. Based on experiment, the finite element analysis was implemented. Results show that the failure is initiated on a certain point near the propellant and the deformation concentration of localization zone and the macro-cracks occur. The failure process can be modeled and stress distributions can be obtained by introducing cohesive element. The method offers references to interface designing
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