## General Mechanical

#### Static Structural Analysis

• rrdbes
Subscriber

Hi I am inputing a new Engineering Material in Ansys workbench. I wonder what could be the required mechanical properties that i'll be needing to test for compressive stress, tensile stress, deflection,  and deformation. Thanks!

• peteroznewman
Subscriber

The simplest and most common Static Structural model can be solved with just the Isotropic Elasticity material model, which requires two property values: Young's Modulus and Poisson's Ratio. With those two values, you can calculate stress and deformation. This is only appropriate if the material you want to simulate is isotropic with linear elastic behavior. There are other material models for other behaviors such as hyperelasticity if you have a rubber material for example.

To evaluate if the stress has exceeded the linear elastic range of the material, you will need to know at least the Tensile Yield Strength. Strength values do not have to be put into the material definition since the calculation of stress and deformation is not affected by them being listed in the material.  If you do add the Tensile Yield Strength value to the material, it is used by the Stress Tool, a result that can include a Safety Factor (SF) plot, which just divides strength by stress so SF > 1 is good (stress below yield), SF < 1 is bad (stress above yield).

• rrdbes
Subscriber

Thanks Peter! I also notice that during simulation at different design loads. And thank you for confirming, i'm havinf hard time because there;s so many variables needed to create a new engineering material. But i guess my simple 2D analysis of roof trusses and my input ultimate strength is enough.

Last question. can i use the total deformation result to calculte the flexural stress on roof element? Thanks!

• peteroznewman
Subscriber

When you assign a linear elastic material to a solid body, that defines the stiffness of the structure. An applied force F will create a deformation x according to F = [K]x where the shape of the geometry and the material's Young's Modulus E define the stiffness matrix [K].

ANSYS solves this equation for the unknown values of x.  Once deformations are known, strains can be calculated. Once strains are calculated, stress is calculated using stress = E * strain. So solving the Static Structural model makes available deformation, strain and stress all at once.

• rrdbes
Subscriber

So, can i use the value of the deformation as the value for deflection?

• peteroznewman
Subscriber

Deformation and deflection mean the same in ANSYS, which is the difference between a node's location before and after loading.

• penguincpj
Subscriber
Hi I am inputing a new Engineering Material in Ansys workbench and running a tensile test simulation to verify the results. I have treated the material as isotropic and defined Young's modulus and poisson's ratio in the engineering data section using my experimental results. nForce acting on the specimen has been defined by x,y,z components in the tabular data. I have retrieved the data from the experiment, copied and pasted it into the tabular data section. Only X [N] increases with time as I am running a tensile test, y and z components remains 0. nThe solution result of the max stress matches pretty well with my experimental results, only slightly higher. However, the solution for max total deformation turns out to be much lower as compared to my experimental results. I'm not sure how to improve the accuracy of the simulation solution nIf anyone knows how to do it, please advise! thank you so much! n