Yile Hu

Bond-based peridynamics with an arbitrary poisson’s ratio

The bond-based peridynamics is modified to remove the constraint on Poisson’s ratio. Bonds connected on a material point are classified as normal bonds and shear bonds. The modification enables the direct use of 2-D plane stress and plane strain constitutive laws for isotropic materials. Engineering constants such as elastic modulus, Poisson’s ratio and shear modulus are utilized in the expressions of peridynamic force density functions for normal and shear bonds. The interaction forces between two material points are determined by longitudinal, transverse stretches and change in angle associated with these two material points. Several simulation results establish the fidelity of this approach.

Peridynamic modeling of defects in composites

This study presents the peridynamic simulation of laminated composites with defects such as delamination and fiber waviness. As part of the peridynamic simulations, an energy based critical stretch parameter is proposed to invoke the effects of different deformation/loading modes. Peridynamic simulations of delamination growth in Double Cantilever Beam (DCB) specimen and laminate with wavy fibers under compression provide both damage initiation and progression. These predictions are compared with numerical and experimental results available in literature; they show remarkable agreement.

Peridynamic Modeling of Cracking in Ceramic Matrix Composites

This study presents a peridynamic modeling approach to predict damage initiation and growth in fiber-reinforced Ceramic Matrix Composites (CMC). Damage prediction is based on the critical stretch which is directly related to the strain energy release rate failure criteria. The capability of this approach is verified against benchmark solutions and experimental observations available in the literature. A new nonuniform discretization capability in peridynamics is applied to investigate crack propagation in CMCs in the presence of a fairly dense matrix, and with fine discretization of the interphase (coating) regions. In the presence of a weak interphase between the fibers and matrix, it predicts the propagation of cracks through the dense matrix while deflecting around the fibers through the interphase region.