Poroelastoplastic modeling of borehole shear bands on high order curvilinear meshes using CUDA technology

<p>The presentation describes an approach to solving problems of modeling the development of zones of localization of plastic deformations within the framework of a poroelastoplastic model generalizing Biot's model. A distinctive feature of this model is a two-way coupling between mechanical processes occurring in a porous elastoplastic matrix and a saturating viscous fluid.</p><p>  For the numerical solution of the problem, a variational formulation based on the Galerkin method and the isoparametric  spectral element method (SEM) is used to discretize the geometric model and PDEs on curvilinear unstructured SEM meshes. SEM orders up to the 15th were used for calculations.</p><p>  The software implementation of the developed algorithm based on SEM is performed using CUDA. A spectral element mesh is naturally mapped to a CUDA grid of SMs, and accordingly, each spectral element is mapped to a streaming block, within which individual nodes are processed by the corresponding threads within the block.</p><p><span>The research for this article is performed partially in Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences and supported by the Russian Science Foundation under grant № 19-77-10062.</span></p>

Assessment of Fiber Stress Based on Elastoplastic Analysis in Discontinuous Composite Materials

An elastopalstic analysis of the micromechanical approach is performed to investigate the stress transfer mechanism in a short fiber reinforced composites. The model is based on the New Shear Lag Theory (NSLT) which was developed by considering the stress concentration effects that exist in the matrix region near fiber ends. The unit cell model is selected as the Representative Volume Element (RVE) for the investigation of longitudinal elastoplastic behavior in discontinuous composites. Thus far, it is focused on the detailed description to predict fiber stresses in case of the behavior of elastoplastic matrix as well as elastic matrix. Slip mechanisms between fiber and matrix which normally take place at the interface are considered for the accurate prediction of fiber stresses. Consequently, onset of Slip points is determined analytically and it showed a moving direction to the fiber center region from the fiber tip as the applied load increases. It is found that the proposed model gives the more reasonable prediction compared with the results of the conventional model (SLT).