Defining Yield Stress for New Material in "Other" Category SAP2000

[maddie_sanders]

Hello,
I am trying to create a new material that does not fall under any of the materials in "Material Type." I therefore chose "Other." However, under "Other" material properties there is no spot to put the yield stress of the location. Because I want to do a crushing analysis of the model, the yield stress is important to define. Does anyone know where to define this? Could I choose one of the material types (even though it isn't correct) and just change all of the properties to match with the material. All of the defined material types have a location for yield stress. However, I feel like this may cause issues and there must be a way to add this for an "other" material.
Any help is greatly appreciated!!

 

[FEA way]

Which software you are talking about ?

 

[maddie_sanders]

Oops I thought I was in a SAP2000 Forum. This is for SAP2000. Do you know how to add a category so this gets seen by the right people who know about SAP2000.

 

[driftLimiter]

Do you want to do a non-linear analysis? You will need to define the hysteresis relationship for the material and use properly selected nonlinear elements. Not sure what you mean by crushing analysis, but you should consider the types of analysis that SAP2000 has to offer and see if you can model your scenario using the available resources.

 

[maddie_sanders]

@driftLimiter
Thank you for your response. I would like to add the compressive and tensile yield strength for my material (which is a 3D printed material). However, this material doesn't fall under any of the material templates and the "Other" template does not have a spot to add yield strength. I am wondering if I can use the Aluminum material template and change all of the properties to match with the 3D printed material. I have attached two pictures, one of the "Other" material template and one of the "Aluminum" material template.

 

[driftLimiter]

Hi maddie I understand that your having trouble inserting the material properties. I strongly recommend first understanding the non-linear capability within SAP 2000. It is not clear to me from your reply what type of analysis procedure you aim to perform. Simply adding the values into the material does not mean that they are going to be used in the analysis. You must first understand what type of anlaysis you want to perform, and then what type of element is needed for that analysis, then what type of materials can be used with that element.

 

[maddie_sanders]

Hello @driftLimiter,
Thanks for your reply. I am new to SAP2000 so I am sorry for some of my lack of knowledge. I have already performed a buckling analysis which did not require the use of the yield strength within the material properties. Now, I am trying to determine the stress within the plates in my model. I believe this would be accomplished by using a linear static analysis (live load case). For this, I believe I would need to define tensile and compressive yield strength. Let me know if this clarifies things. Sorry again for my lack of proficiency in SAP

 

[driftLimiter]

Its okay to be new at something lol, you have to recognize the things you don't know and the things you do know in structural engineering...

I think you need to do some learning regarding linear, and non-linear structural analysis techniques (sap can do both). Also a bit of mechanics/statics/general structural analysis.

For linear analysis, all of the material is assumed to remain elastic. That means that linear analysis does not capture buckling, crushing, tensile yield, or really any failure.
The key to linear analysis, is that the assumption is that all materials remain elastic and their section/material properties remain constant.
The results of the linear analysis can be taken from the program and compared with the material allowable stress levels manually by the user. You might find that some of the stresses inside the modeled elements are higher than the allowable stresses and this should cause a redesign or reconfiguration.

For example if you pull a spring and it snaps back to it's original location each time, the material is remaining elastic.

Sap has some built in strength checks for standard construction materials. Not for custom materials.

Non-linear analysis on the other hand is a type of analysis that allows the material properties to change as a function of the loading history.
For example if you pull on a spring too hard, so much that it does not return to it's original position, this is a nonlinear effect.


I can suggest that stay in the realm of linear elastic analysis. You need to only model the geometry and a few material properties to run this model. The next step is to extract the internal stresses of the elements in your model and manually compare them with the allowable stresses you have.

Stresses in the model that are well below the allowable signify elastic behavior. If the model stress is way over the allowable then its probably failure.

You should try to dial in the Modulus of elasticity of your material. This is the main material property that will effect the accuracy of the model.

Perhaps some time spent learning general Sap2000 with typical materials will go a long way for you. The modeling of this unique material is a more advanced application of sap.

Best of luck