Papers by Author: Hui Miao

Abstract: A technique for non-contact optical measurement of in-plane displacements based on correlation analysis is presented. This approach can be used to identify the position of a marker before and after deformation of a specimen or plane test-object. Some mechanical parameters of materials and strains can be calculated using information from several markers’ displacements. The method is simpler than other optical techniques in experimental processing and can efficiently used to measure large deformations. The precision of marker identification method is analyzed. And some discussion on this method is also given.

Abstract: A series of numerical meso-mechanical models for different kinds of particle (include spherical, cylindrical and discal) reinforced composites are developed to investigate the effect of microstructural parameters on the elastic properties of composites. In these models, an effective interface concept is adopted. Finite element models with prescribed and random parameters are automatically generated in ABAQUS PDE (Python Development Environment). In the simulative investigations, it is observed that the degree of particle clustering and particle’s shape have strong effects on the elastic mechanical properties of composites.

Abstract: As a universal finite element method commercial software, ABAQUS has been widely used in scientific research and engineering applications. However, convergence difficulties are familiar issues while carrying out damage and fracture analysis. Several methods, which are helpful to avoid these convergence problems, are presented in this paper. Baseline simulations about damage initiation and propagation in composites indicate that a larger value of viscous regularization causes the peak of the reaction force to be higher. A smaller viscosity parameter is better than bigger one. Other advanced techniques, include using automatic stabilization and customized general solution controls, are adoptable to improve convergence in ABAQUS/Standard analysis. The results of the paper are expected to provide guidance for the new user of ABAQUS.

Abstract: The mechanical behaviors of Nylon6 polymer film material are investigated experimentally. A technique, marker identification method, for non-contact optical measurement of in-plane displacements based on correlation analysis is employed to measure the deformation of the film specimens. Based on the uniaxial tension experimental results, the stress-strain relationship is obtained, which result in Young’s modulus and the Poisson’s ratio. In the creep experiment, the time-depending response of polymer film material is studied. The strain state is determined by measuring the deformations over time. Based on the obtained data about the material’s response, the bulk-modulus K(t) is calculated based on BOLTZMANN’s superposition principle.

Abstract: Damage initiation and propagation in unidirectional glass fibre reinforced epoxy matrix composites under tension load were simulated in this study. Cell models with either single fibre or multiple fibres were modelled by extended finite element method (XFEM). The damage progress in the cells was investigated and then the nominal stress-strain curves as well as stress distributions in the fibre and matrix were obtained. Results presented here indicate that the extended finite element method is an effective modelling technique to study the initiation and propagation of a crack along an arbitrary, mesh-independent, solution-dependent path.