the size effect on material propties in Abaqus

[Mohamedsayed]

Hello everyone,

I am simulating an underground mine. The mine is similar to surface structure (building), it has columns and roof.

I need to use Abaqus to simulate the mine, but i have a problem with the material properties, Both the ultimate strength and behavior of the stress-strain diagram are affected by the size of the specimen.

so the peak strength of the material which represents the column in the mine is affected by the dimension of the specimen.

I am confuse about how to input the material properties in abaqus since the size of the tested specimen has an effect of the stress-strain curve.

Is there any ideas about how can i overcome that problem.

 

[Mohamedsayed]

Hello
Is there any advice?
Thanks

 

[IceBreakerSours]

..the size of the tested specimen has an effect of the stress-strain curve.

This reflects a gap in theoretical understanding; grab a good undergraduate textbook and refresh your basic theoretical background.

As the name suggests, "material property" is not specimen or geometry specific; it is the inherent property of the material. For example, the Young's modulus remains the same (within an error bound) for a given material as long as the loading rate, temperature, specimen orientation, etc. remain unchanged. That said, with the same amount of material, one can make shapes of varying stiffness (which changes with geometry) under a type of loading depending, for example, on the cross-sectional area and cross-sectional shape. Stiffness and Young's modulus are not the same thing.

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