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Hi all,

I've been facing a very strange problem now when I'm using abaqus to finish RVE multiscaling simulation: so far, what I've done is successfully linking fortran and abaqus to run the whole calculation. At first, I met a small problem--- overwrite the old files(y/n)?---which has been solved by adding a "abaqus_v6.env" file whose content is as follows in the abaqus working direction:

ask_delete=OFF

Hi all,

anybody knows about a good introductory book in the field of Strain Gradient and Couple stress theory?

Hello everyone

I am modelling a horizontally curved steel beam under uniform moment. I can tell the beam is under uniform moment because the S11 stress is uniform along the beam. The problem is that the lateral and torsional deflections are very low. For instante, if I apply the critical moment to the beam it only deflects 20 cm (lateral deflection) and I expected larger deformations when the beam buckles. 

Hello all, 

I am a beginner in UMAT implementation. I want to implement a Umat soubroutine for a kinematic hardening model using Hill's yield criterion. However, after looking in different courses and books, I remarked that the jacobian matrix derivation steps from the constitutive equations are not explicitaly defined.

Can anyone help me to understand this derivation step so that I can apply it for the Hill's criterion ?

Thank you in advance,

Regards,
Haithem  

Hi everyone, 

I am trying to model an experiment (axial loaded concrete column). 

How can I make my load-deflection curve from the FE-model to get closer to the curve from the experiment? 

Thanks! 

Dear iMechanica users,

I am working on a metallic foam model, and due to its nature of geometry and physical properties, I considered geometrical and physical nonlinearities. What is the significance of NLGEOM = ON and NLGEOM = OFF besides, it includes or excludes the geomterical nonlinearity in ABAQUS? I want to know the basic change that has been incorporated when I switch the NLGEOM between ON and OFF. Also, a theoretical explanation on how this change is caried out. 

I am currently in my Master Degree in Civil Engineering at Andhra University  I am doing a research on concrete wrapped CFRP sheets and I want to do Finite Element Analysis using ANSYS. I am not able to model concrete in ANSYS. Can anyone please help me out with that.

Awaiting the reply....

Hello everyone,

I  modelled  a slender beam (an Euler-Bernoulli beam)  in flexural vibration in Abaqus  in order to do a natrural frequencies extraction. And, then i wanned to analyse the impact of a concentrated mass in its end. but for the first mode, i obtained a result understandable but not for the following modes which i verified analytically. the viewport of this fundamental mode can be found as a file attachement.

Could you please give me an explanation. And Thank you very much for your help

Hello everyone,

I am modelling a rectangular cross section beam in Abaqus using shell elements (S4R) in order to study its lateral and torsional deformation. I am trying to apply a uniform moment (Mo) to the beam by applying compressive forces in all the end nodes avobe the neutral axis and tensile forces in the end nodes below the neutral axis. I can tell this is not working because the Abaqus results for vertical displacement do not match with the analytical results of the next equation: y''=Mo/EI

i m working in analytical assesment of blast loads on rcc structure in ansys civil fem ..but i am confused whether i am getting corrrect deformation or not ..i am in need of help