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Analysis of the adsorption-induced deformation of ordered meso/nanoporous materials

The pore-load modulus of ordered nanoporous materials with surface effects.

Liu, M., Wu, J., Gan, Y., Chen, C. Q. AIP Advances, 2016, 6(3):813. http://scitation.aip.org/content/aip/journal/adva/6/3/10.1063/1.4945441

A feasibility study of the Master SN curve approach for short fiber reinforced composites

I hope you find our recent work interesting...

A feasibility study of the Master SN curve approach for short fiber reinforced composites

Atul Jain, Wim Van Paepegem, Ignaas Verpoest, Stepan V. Lomov

International Journal of Fatigue; Volume 91, Part 1, October 2016, Pages 264–274

http://www.sciencedirect.com/science/article/pii/S0142112316301591

Highlights

Emilio Martínez Pañeda's picture

Strain gradient plasticity-based modeling of hydrogen environment assisted cracking

I hope some of you may find this work interesting:

Strain gradient plasticity-based modeling of hydrogen environment assisted cracking

Emilio Martínez-Pañeda, Christian F. Niordson, Richard P. Gangloff

Acta Materialia, 117, pp. 321-332

http://www.sciencedirect.com/science/article/pii/S1359645416305183

A pre-print is available at www.empaneda.com

maharshi.kintada's picture

What modifications are to be implemented, if the shear strain of a degenerated shell element is modified with (-2*w/Rxy)?

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I had implemented Degenerated shell element by Ahmad et. al (1970). This element performs very poor in case of geometries like rectangular hyperbolic paraboloidal shells. When I modified the strain vector (only shear strain) with a additional -2*w/Rxy (Sahoo and Chakraborty, J. Strain Analysis (2004)), the solutions are not ok. Can you please suggest me if any other things I should be careful?

UMAT for uniaxial compression (plasticity)test is not converge

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Hello everyone,

I am beginner of UMAT.

I am now modeling the model for uniaxial compression of shape memory alloys based on plasticity model and backward euler method.

My material is in cubic 1*1*1. It seems to be simple problem.

Anyway, I am still not familiar with UMAT and Abaqus.

The problem is I apply load just only in Y-axis and specify the boundary condition as in attached file

I think that it passed the plastic deformation zone and abaqus try to calculate...

Call for Papers // Fatigue Durability India 2016 // Publishing Partner Springer

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FatigueDurability India 2016 invites technical papers from all Academicians/ individuals/companies associated with engineering design, analysis, testing, instrumentation, research on Fatigue Durability & Fracture Mechanics or related technologies .

The Authors are encouraged to submit paper on the following themes, but not limited to

Looking for a postdoc research position in solid mechanics

My name is Zhan Zhixin and I got my PhD diploma of solid mechanics at Beihang University at January 16th, 2016. Now I'm looking for a postdoc research position in solid mechanics.

My Ph.D research program is about the experimental method for and theoretical research on the fatigue life calculation of defected structure based on damage mechanics, which focus on the fatigue failure analysis of metallic materials with impact or scratch defect considering residual stress, plastic damage and fatigue damage.

My research interests contain the following two aspects:

Jingjie Yeo's picture

Effects of Nanoporosity on the Mechanical Properties and Applications of Aerogels in Composite Structures

Newly published book chapter - http://link.springer.com/chapter/10.1007/978-3-319-31662-8_4 Aerogels are ultralight solids with nanoporous structure and are one of the world’s lightest materials available in the market. It is a dry gel, principally made up of 99.8 % of air and weighing just around three times that of air. The first aerogels were realized in 1931, when Kistler (J Phys Chem 36:52–64, 1932) attempted to remove liquid from a wet gel.

Jingjie Yeo's picture

Effects of Nanoporosity on the Mechanical Properties and Applications of Aerogels in Composite Structures

Newly published book chapter - http://link.springer.com/chapter/10.1007/978-3-319-31662-8_4 Aerogels are ultralight solids with nanoporous structure and are one of the world’s lightest materials available in the market. It is a dry gel, principally made up of 99.8 % of air and weighing just around three times that of air. The first aerogels were realized in 1931, when Kistler (J Phys Chem 36:52–64, 1932) attempted to remove liquid from a wet gel.

Regarding Node based Submodeling

Hello Everyone,

 

I am trying to understand how does node based submodeling work in abaqus? I am not able to comprehend how to transfer nodal outputs from some other FEM package so as to perform submodeling in Abaqus? Any help in this regard is highly appreciated.

Multi-scale modeling of plastic deformations in nano-scale materials; Transition to plastic limit

Despite the controversial debates concerning a unified theory, the continuum plasticity has evolved during the last few decades and an uncountable number of articles has been published on the subject. The proposal of Lee to decompose the deformation gradient, F, into elastic part Fe and plastic part Fp (i.e. F=FeFp) combined with the principle of maximum plastic dissipation is used in many publications to formulate the ensuing developments.

marco.paggi's picture

Structural mechanics models for renewable energy applications

Dear Colleague,

the output of the FIRB Italian Project in the object (Politecnico di Torino, University of Salento and University of Trento, 2012-2016) has been published on the following permanent webpage:

http://musam.imtlucca.it/FIRB.html

Models and applications regard photovoltaic modules, solid oxide fuel cells, and piezoelectrical systems for energy harvesting.

Yours sincerely, 

Marco Paggi 

Principal Investigator 

 

 

 

sol (amount of solute in entire model)

hi

during a mass diffusion step, what is the unit of the history output sol (amount of solute in entire model)?

any help is appreciated

Ajeet Kumar's picture

Effect of material nonlinearity on spatial buckling of nanorods and nanotubes

You may be interested in reading our following article: http://link.springer.com/article/10.1007/s10659-016-9586-1. We show the importance of incorporating material nonlinearity for accurate simulation of nanorods and nanotubes. The linear material laws are shown to give completely erroneous results. The nonlinear material laws for nanorods were obtained using the recently proposed "Helical Cauchy-Born rule". We also discuss how surface stress affects buckling in such nanostructures.

Hidroxid's picture

XFEM crack under compression.

Hi all,

 

I am doing crack modelling (XFEM) under moving compression and traction loading in Abaqus but I get warning regarding the crack under compression load as follows:

"THE LOADING CONDITION MIGHT MAKE MAIN CRACK UNDER COMPRESSION AT  NSET "X" THE CRACK PROPAGATION DIRECTION CANNOT BE PREDICTED. A VALUE OF ZERO IS PROVIDED FOR IT."

Anyone facing the same issue?

Kind regards,

Omid

SamInfinity's picture

ABAQUS: problem in applying pressure after element deletion

 In ABAQUS, how to apply a pressure field using vdload subroutine on a newly produced surface after deletion of elements from the top surface where the pressure field was actually applied? Or in other words, how to define a new surface for applying a pressure field, where the surface on which the pressure was initially applied is deleted with the evolution of damage. 

Wenbin Yu's picture

RVE analysis without BCs and periodic mesh requirements

RVE analysis becomes a routine exercise in material modeling. Usually it is carried out using finite element codes such as ABAQUS or ANSYS. The main thing one should pay attention is to applying the right boundary conditions. It is settled that periodic boundary conditions are the preferred boundary conditions to be applied. The BCs are that u_i-\epsilon_{ij}x_j should be equal on the corresponding edges. This type of boundary conditions can be applied using coupled equations constraints. This requires that one creates a mesh with corresponding nodes on periodic edges.

Flavio Stochino's picture

RC beams under blast load: Reliability and sensitivity analysis

The effects of blast loading on structures can be very dangerous: damages and failures are expected with serious threats to structural safety and human life. Materials stresses and strains are often pushed to the limit and the modelling of these phenomena can be very complex. In order to design blast-resistant structures it is very important to determine what are the key parameters of this problem.

 

ABAQUS, DLOAD, new active load surface, element deletion

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Dear all,

Currently I am engaged in solving a geological problem. So we have some soil model in the form of disk, there is a circular hole in the center, which has the initial pressure at the reference time  (a modelling of the soil injection with the polymer compound)

How can I recalculate the normal pressure inside the circular hole of the soil model using the DLOAD subroutine if the neighbouring FEs were failed.

Mirkhalaf's picture

RVE size determination

The definition of the size of the Representative Volume Element (RVE) is extremely important for the mechanics and physics of heterogeneous materials since it should statistically represent the micro-structure of the material. In the present contribution, a methodology based on statistical analysis and numerical experiments is proposed to determine the size of the RVE for heterogeneous amorphous polymers subjected to finite deformations.

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