Learning Forum

[RobertoLucena]

Hello,

I´m working on a project and the main problem is compare two types of soil modelation: using the youngs modulus and using elastic support.

I have noticed that i cant change the configuration of the elastic support. How can i do to manipulate this tool?

[peteroznewman]

Here is the ANSYS Help definition of Elastic Support:

Allows one or more faces (3D) or edges (2D) to move or deform according to a spring behavior. The Elastic Support is based on a Foundation Stiffness set in the Details view, which is defined as the pressure required to produce a unit normal deflection of the foundation.

The direction of the springs is normal to the face.  This support provides no lateral constraint, which is why your disk model wouldn't solve until you used 2 symmetry regions to support the lateral DOFs.

You want to compare Elastic Support with using a second body that has a Young's Modulus. Let's not forget that a second body will also have a Poisson's Ratio. If you put a slab of material Top adjacent to a slab of material B you have two choices, they can be bonded, or they can have a frictional contact. If they are bonded, then the Poisson Ratio is going to cause the material B which is being compressed, to spread, and apply some tension to the slab on Top. If you use frictional contact, you can limit the tension force. If you use Elastic Support, there is no spreading and no lateral tension.  You could get the same effect with a frictionless contact.

[RobertoLucena]

Hello Peter,

I understand now how it works, but I wanna know if is possible to change the number of springs on the element? Is one spring for each node?

I will start to manipulate the soil with the Youngs Modulus soon, I have one article wich gives me some results that I can base my research on. I will probably have more doubts about it later.

[peteroznewman]

Yes, one spring for each node. All you can change is the Stiffness value.

[RobertoLucena]

Ok, Thank you, that is the solution.