ResearchList of all research projects
Higher-order stress-based gradient-enhanced damage model using isogeometric analysis for shell delamination analysis

Higher-order stress-based gradient-enhanced damage model using isogeometric analysis for shell delamination analysis

Led by:  X. Zhuang
Team:  Thai Q. Tran
Year:  2016

The micro-damage associated with diffuse fracture processes in quasi-brittle materials can be described by continuum damage mechanics. In order to overcome the mesh dependence of local damage formulations, non-local and gradient-enhanced approaches are often employed. In this project, a higher-order gradient-enhanced formulation is developed, which exploits the higher-order continuity of Non-uniform rational B-spline functions (NURBS) in isogeometric analysis (IGA) for delamination analysis of shell structures. The work aims to demonstrate that using IGA enables an elegant approach to implement the Kirchhoff-Love shell formulation for thin wall structure analysis where the C1 continuity is required for the stress resultant formulations. In order to describe the discontinuities across different layers in multilayer composite shells, interface element is embedded into the continuum domain as a natural mean with an appropriate constitutive relation. Numerical results will be compared and validated with experimental data of some benchmark problems to demonstrate the suitability of the proposed model.

Figure 1. Evolution of damage for a three-point bending beam with the formulation of damage model. Displacements are 50 times amplified.

Figure 2. Deformation of a beam at different loading steps using cohesive zone model for delamination analysis.