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[Webcast] Nuclear Power - from Last Gasp to Second Wind

Submitted by imeche on

This lecture reviews the tumultuous changes taking place in the nuclear industry; from its enthusiastic beginnings, through the darker days and on to the current resurgence. It explores the future of nuclear power as a major solution to energy security and climate change issues.

How to explain the limit load by stiffness matrix using finite element analysis?

Submitted by pfliu@zju.edu.cn on

I always have a question about the convergence problem: when a structure reaches its maximum load-bearing ability, the solution will end if the newton method is used in the finite element analysis. Then which form the stiffness stiffness in the finite element analysis takes on?  Singular or ill-conditioning?  How to explain the appearance of maximum load by variable stiffness matrix?

Young's modulus

Submitted by wanbot on

Hi all,

I have this confusing thought for a quite long time. 

Is there any relation between the time-independent Young's modulus with the time-dependent Young's modulus (instantaneous and equilibrium moduli or loss and storage moduli)?

If yes, what is the equation to relate them?

So many terminologies which make this confusion!

Please help.

Wanbot

 

 

UMAT subroutine in ABAQUS for elasto-plastic cyclic loadings

Submitted by bojan on

I want to implement the elasto-plastic model for cyclic loadings (I suppose
something like chaboche) into the UMAT subroutine in my ABAQUS  model ,
but I haven't enough knowldge for do this. I read some book like mechanichs of solid materials but i don't understand how to implement my constitutive law into the subroutine. until the load is static i don't have many problems, but when i work with cyclic load I'm non able to generate a cyclic increments of plastic behaviou.

Modelling Hyper-elastic Plate Using ABAQUS

Submitted by J Mahmud on

Dear All,

For months, I have tried to model a plate with circular hole which has the properties of hyper-elastic material (Ogden) but the results are still not promising compared to literature (Y Basar 1998).  The main problems are:

1. The maximum load I succeeded to apply was q=26, while literature had applied load up to 90. For q > 26, the analysis will terminate with errors such as too many attempt, excessive distortion etc.

2. The results I get for q<26 are not the same as literature. 

I attach my best result for your viewing.