research

http://stephanebordas.blogspot.co.uk/

Simple finite elements based on Timoshenko beam and Mindlin plate theories have been developed for the analysis of thick and thin structures (beams and plates) using standard finite element procedure. These elements have 3 dof and a new concept, Convergence Factor, is introduced in the formuation to accelerate convergence keeping the number of elements constant. No shear correction factor is used and no shear lock problem is encountered.

Subramanian

Hello,

I am modelling a crushing simulation of a composite corrugated coupon using Abaqus/Explicit and CZONE Abaqus' application.

I am modeling the coupon using S4R elements and the impactor as a discrete rigid shell plate with a slow constant crushing speed or high initial velocity for quasi-static and dynamic crushing simulations respectively.

I am using Hashin damage in Abaqus/Explicit and Hashin and also Tsai-Wu on CZONE application.

I have a one dimensional bar with a triangular pulse given at one end for 2 microseconds. The boundary conditions are free-free.I am having two cases. One in which the deformation is local (Hooke's law) and other in which the deformation is dependent on a kernel of radius r (say 5* element length).I find that the wave speed is higher when the deformation is non-local as compared to local deformation case. Is this correct? Is there a way to verify the solution?

Hello All,

Currently, I am trying to model a layered beam one on top of other. I started with 3 layers with leaving a small gap (0.01 mm) in between. I am interested in connecting the nodes of top layer (one line representing a beam) to the adjacent beam having same number of nodes through beam elements. To be more clear, merging nodes with same element type connectivity (beam to beam).

 1) anaylitical model:

Vertical Cylindrical beam under axial compression load

Height: 26.5mm, Radius: 1.25mm, E: 200000, Load factor k: 2,
Pcritical: 1,347N, Displacement: 0.0364mm 

 2) Beam188 model worked fine with results similar to
analytical one. (txt file attached)

3) Solid186 mold under predicts by a factor of 4 (txt file
attached)

why does the solid 186 element give different results?

Thanks

H Jishi 

In this movie taken at 1 Mfps using our new Kirana camera (courtesy Y. Rotbaum), one can see a dynamic tension test of a grroved specimen in a tensile Hopkinson bar. The groove is relatively sharp and 10% of the diameter in depth.

It so happens that the dynamic neck inception occurs outside the notch area, in other words a strong geometrical flaw does not dictate the failure locus. We have performed over a hundred of such experiments. This is a very interesting and challenging observation....