Start by learning how to create a RCC beam in ANSYS with the proper material properties that will provide the softening behavior that will deliver an ultimate load point in the load-deflection curve.
Here is a good discussion on concrete models.
Here is a post with links to three discussions on SOLID65.
Softening behavior refers to the damage that occurs in the stress-strain behavior of a concrete material. Please go through this article for some additional description.
Now, when you have this behavior included you would see a load vs deflection as discussed in this paper, which helps you determine the ultimate load vs deflection.
Hope this helps.
TB = table and is used to send a table of values to a material model. The specific meaning of the values after TB depend on the preceding command.
Here is a relevant post.
These values correspond to what is in the TB command. So depending on that, the TBDATA would point to different material parameters such as poisons ratio, yield stress etc. Now in your case, it looks like 1 corresponds to the first data point and 0.3 to the poisson's ratio. Checkout this part of the manual for understanding material data tables.
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