Surface Elastic Boundary Stiffness

[ishvaaag]

I am just starting to dabble with Algor and in SI a N/mm elastic boundary stiffness is stated for surface elements. Is this stiffness that expected to be presented by 1 mm2 or for the whole surface area?

 

[ishvaaag]

I will make a stiff plate model and guess the nature of the stated stiffness, but it would be nice to have a statement on what above... Thanks beforehand.

 

[ishvaaag]

I have made a model with a stiff model and the conclusion I reach to is that ALGOR applies the elastic boundary stiffness stated in the box in N/mm as spring constant of each and every node in the face to which the elastic restraint is applied. This is a very DISTURBING conclusion for those wanting to use spring constants with ALGOR and automatic mesh generations, since one loses control of the number of vertices generated, or may need always to be attent to the question. Furthermore, the irregular meshes would be such spring constants inadequate to the intent.

The morale here is that one should forfeit to make ordinary spring constant models for foundations in ALGOR. Use instead a ground material on a fixed base and then calibrate the investigated response to your intent. Bad (and very good) in that it makes too much explicit the shortcomings of the investigations of the structural effect of expected settlements.

 

[ishvaaag]

errata

Furthermore, with irregular meshes that would make such spring constants inadequate to the intent.