Analysis of large deformation of elastic-viscoplastic materials has been performed in this paper using the finite element method with the arbitrary Lagrangian-Eulerian description. An overstress type viscoplastic model using the internal variable approach in a rotated stress-strain space characterizes the material. Stable and efficient integration techniques for the viscoplastic relations are d...

The biomechanical behavior of tissues under mechanical stimulation is critically important to physiological function. We report a combined experimental and modeling study of bioengineered 3D smooth muscle microtissues that reveals a previously unappreciated interaction between active cell mechanics and the viscoplastic properties of the extracellular matrix. The microtissues' response to stretc...

In this paper we study a numerical method for the simulation of free surface flows of viscoplastic (Herschel-Bulkley) fluids. The approach is based on the level set method for capturing the free surface evolution and on locally refined and dynamically adapted octree cartesian staggered grids for the discretization of fluid and level set equations. A regularized model is applied to handle the no...

Shoulder geometry of tool plays an important role in friction-stir welding because it controls thermal interactions and heat generation. This work is proposed and developed a coupled rigid-viscoplastic numerical modeling based on computational fluid dynamics and finite element calculations aiming to understand these interactions. Model solves mass conservation, momentum, and energy equations in...

A new elastic-viscoplastic (EVP) constitutive model is proposed for the analysis of time-dependent behavior of clay. The proposed model is based on the bounding surface plasticity and the concept of viscoplastic consistency framework to establish continuous transition from plasticity to rate dependent viscoplasticity. Unlike the overstress based models, this model will meet the consistency cond...

This paper aims to develop a numerical multiscale homogenization method for prediction of elasto-viscoplastic properties of a high performance concrete (HPC). The homogenization procedure is separated into two-levels according to the microstructure of the HPC: the mortar or matrix level and the concrete level. The elasto-viscoplastic behavior of individual microstructural phases of the matrix a...

In hot forming process, the workpiece undergoes plastic deformation at high temperature and the microstructure of the workpiece changes according to the plastic deformation. These changes affect the mechanical properties of workpiece. In order to optimize this process, both the plastic deformation of workpiece and its microstructural changes should be taken into consideration. Since material be...

This paper reviews the performance of two time-dependent constitutive models in predictions of one-dimensional consolidation. The Soft-Soil Creep model [1] is an example of an elastic-viscoplastic formulation that incorporates a timedependent state variable to estimate viscoplastic deformation. We show that the SSC model is equivalent to the isotache formulation proposed by Imai [2], as both ar...

Simulations of viscoplastic materials are traditionally governed by continuum mechanics. The viscous behavior is typically modeled as an internal force, defined by diverse quantities. This work introduces a fluid model to simulate the viscoplastic effect of solid materials, such as plastic, wax, clay and polymer. Our method consists in modeling a solid object through a non-Newtonian fluid with ...

In hot forming process, the workpiece undergoes plastic deformation at high temperature and the microstructure of the workpiece changes according to the plastic deformation. These changes affect the mechanical properties of workpiece. In order to optimize this process, both the plastic deformation of workpiece and its microstructural changes should be taken into consideration. Since material be...