Hi,

I was going though papers related to micromechanical modeling of composites using unit cell approach. Usually in this procedure, a unit cell is isolated from the material and to ensure the compatabilty of the unit cell boundary, periodic boundary conditions are applied.

To ensure the compatabilty of the boundary and to apply loads, can we use submodeling techniques available in ABAQUS.

Thank you

Regards

Ghouse 

Hi,

I have modeled a two phase unit cell with one inclusion in a soft matrix. I have applied appropriate periodic boundary conditions. Load is applied a displacement. I have solved the problem using FEA through ABAQUS. Now I want macroscopic stress-strain response of the material.

What I have done is, taken the Reaction force and divided it by the area and similary displacement and didvided by length, will this give me the stress-strain response or do I have to use some homogenisation methods.

Thank You

Regards

Ghouse

Hi,

I am modeling interface, its thickness is around 100 micron, I am modeling this problem in ABAQUS, my doubt is, can I use continuum elements like plane stress or plane strain to model this interface with conventional materail models available in ABAQUS or do I have to use interface elements with cohesive zone models. My main doubt is why should I use interface elements, whether plane or solid elements cannot handle interface, please can any body educate on this topic.

THank you

Regadrs

Gouse

Hi,

I observed that with
periodic boundary conditions on unit concrete unit cell, when uniaxial load is applied structure
behaves as if it is constrained to move in lateral direction, when
shear or other traction laoding is applied it has displacement
compatible behavior i.e, parallel edges has periodic deformation
behavior. With these above behavior can I conclude that for uniaxial
loading I need not apply periodic BCs and simply applying roller is
sufficient on lateral edges or there is no need to apply and periodic
BCs for uniaxial loading.

Dear All,

I am trying to simulate mechanical behaviour of a concrete unit cell for uniaxial compression laoding. I have apllied periodic bounadary conditions on both lateral edges using linear equation option available in ABAQUS where as on top and bottom edges load is apllied. Deformed structure shows there is no lateral deformation and unit cell behaves as if it is confined laterally on both sides. I am confused about my boundary conditions whether they are correct or not. 

 Equation used to aplly periodic bounadary condition are

Hi,

Gouse 

Hi,

I have square plate with circular inclusion, I have added a cohesive elements around the inclusion. Inclusion is harder and matrix is softer. I have applied both tensile and compressive loads on tha plate, I could able see debonding for tensile loading but i could not see debonding fro compressive load. I am using maximum stress criterion for damage initiation and for damage evolution fracture energy. I am doing simulations in Abaqus. Now I want to replace normal stress criterion by some shear criterion, can I able do it. Is there any shear based crietrion for cohesive zone modeling.

With Warm regards

Gouse

Hi,

I am simulating failure of concrete in tension and compression on a concrete representative element volume. I have modeled mortar matrix and aggregate (inclusion) separately i.e my model consists of two material and assumed them as perfectly bonded. My question is, if I add interface zone between matrix and inclusion how will it effect my overall failre or can I neglect inerface.

With Warm Regards

Gouse

Hi,

I want to know what is the effect of coarse aggregate size or size of the aggregate on compressive strength of concrete.And similarly what is effect of aggregate size on tensile strength of concrete.

I have few papers which contradicts each other so I am confused.

With Warm Regards

Gouse

Hi all,

 I want to plot nominal stress Vs nominal strain plot from my FEA simulation. In generally I will get stress and strain at element level, now how can I plot stress-strain for the overall struture. I am applying uniaxual load on specimen. My analysis is non-linear.

Thank you

Regards

Gouse

Hi,

 I want to simulate filaure in cement mortar. I am using Rankine criterion for detecting failure. For propagating damage i want to soften element. Here can I suddenly reduce the stiffness of the element to a negligible value as soon as it reaches specified failure criterion. I read in some book about mesh sensitivity in stress based failure criterion but i could not understand.Can some body expalin what is its consequence of suddenly reducing stiffness of element to a negligible value. How mesh will effect.

With Best Regards

Gouse

Hi

I am trying to predict load-displacement curve for concrete cube numerically through ABAQUS. I am just beginer with ABAQUS, I have gone through the concrete material models available in ABAQUS. I found that smeared crack model well suite for analysis. Initially I am simulating a 2D model, I am using plane stress elements with static, Riks options, even I could able to complete the analysis, I am confused how to view the cracked elements and how to plot load-displacement curve.

I want to know whether I am going in a right path by using smear cracking model for crack propagation.

Thank you for your reply

Regards

Gouse