• dcc
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  • Registered: 2020-04-24
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Topic: Plastic strain

Dear all,

Since I am using material parameters based on my experimental investigation, I have question regarding value of plastic strain at compressive strength. According to the theory manual and explanation of the parameter in Atena Science GiD interface, it can be calculated based on following formula FC/E. However when I am checking the formula according to the default Concrete EC2 materials I am not getting the same value. Consequently I used default value for matching concrete class with my examined materials. But I have Young's modulus value in case of one material subsequently lower so I would like to check how the value can be calculated.

Quote Post 1

  • dpryl
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Re: Plastic strain

Dear dcc,
the default formula for eps_cp follows the EC formula, setting the plastic strain at compressive peak equal to the elastic strain at the same point. In other words, at peak compression, the elastic and plastic strains are each 1/2 of the total strain.

If you change the elastic modulus after generating the material properties, it makes sense to adjust the eps_cp manually.

If you suspect the generated value does not correspond to the formula in the documentation, please tell us what option (compressive strength or concrete class) and values/settings you have used for the generation, and what is the generated and expected eps_cp such that we can check here. 

Regards.

dpryl's Website

Quote Post 2

  • dcc
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Re: Plastic strain

Dear dpryl,

If I use C35/45 for example concrete class and generate material properties for the mean safety format. E=34000 MPa and FC=-43 MPa, and EPS CP is -0.00098162. This does not correspond to provided formula FC/E. I guess I am understanding smth wrong.

Quote Post 3

  • dpryl
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Re: Plastic strain

Dear dcc,
thank you for the problem report, I have forwarded it to our colleague responsible for the ATENA-GiD scripts, such that he can try to reproduce and fix the scripts or the documentation if needed. He may contact you for additional details (your exact ATENA version or similar).

Regards.

dpryl's Website

Quote Post 4