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Hello,

I am trying to evaluate the behaviour of a 2D plain strain "cut and cover" tunnel section when I apply static loads (by the moment)

I am using XFEM method in order to evaluate the cracks through the reinforced concrete material. The model has been meshed by CPE4R elements (Quad)

I have modelled 2 types of steps: Geostatic in order to apply the initial stress state and Static, general for the rest of steps.

I am trying to solve the error below:

A xfem analysis with pore pressure degrees of freedom is not supported.

Hi Sirs,

As title, I wondering if the problem can be solved with only material residual stress but no other external load applied?

After several trials, Abaqus returns message
"MASS OR DIFFERENTIAL STIFFNESS MATRIX IS COMPLETELY NULL. THE EIGENPROBLEM CANNOT BE SOLVED. IN A *BUCKLE ANALYSIS THE MOST LIKELY CAUSE IS THAT A NONZERO LOADING PATTERN WAS NOT SPECIFIED VIA *BOUNDARY, *CLOAD, *DLOAD, ETC,. SEE Eigenvalue Buckling Prediction IN THE ABAQUS/STANDARD USERS MANUAL"

Hello All,

For the Cattaneo's hyperbolic heat equation with relaxation time,

usually a simple plane thermal wave Τ=T0 * exp[ ¡ (kx - ωt) ], with definition k is the (complex) wave number and ω is the the (real) frequency, is adopted to obtain the dispersion relations of the heat equation.

And consequently, the velocity is defined as: [ω / Re(k)].

My confusion is that is it necessary or obligatory to let k be complex and w be real?

If the answer is yes, then why?

If no, then it's possible to let both k and w are real?

Hello, I'm trying to program a quadrilateral classical Mindlin flat shell element (full integration for membrane, bending and selective reduced integration for transverse shear).

Now, the situation is: 
for pure tension test, it works well (because only the membrane part works),
for pure bending test, it gives very bad result compared with S4R, and I find that's because the incremental rotations at each step are different.

We're running a series of free workshops at the AMP Technology Centre in Rotherham (June 27th), the University of Liverpool (June 28th) and the University of Leeds (June 29th) this month, where we'll be explaining the benefits of Simpleware for working with 3D image data.

Dear Colleagues,

A brand new Siconos 4.0.0 is out !! Siconos is now distributed under Apache 2.0 license.

What is Siconos ?

Siconos is an open-source scientific software primarily targeted at modeling and simulating nonsmooth dynamical systems in C++ and in Python:

 + Mechanical systems (rigid or solid) with unilateral contact and Coulomb friction and impact (nonsmooth mechanics, contact dynamics, multibody systems dynamics or granular materials).