Calibration of microscopic parameters

[LE Ba Danh]

Hello everyone,
I need to simulate 2 test with Granoo:
1. The compression test on a cylindrical of Ultra-High Performance Concrete (UHPC).
2. Bending test on a concrete beam of Ultra-High Performance Concrete (UHPC)
I found an article that uses the Lattice Discrete Particle Model to simulate cracking of these test (photo attached)



- Did you introduce the elastoplastic models in Granoo 2.0 to model materials like concrete?
- To model the fracture in compression test, I need introduce the microscopic compressive strength of cohesive beam in Granoo, the calibration procedure of this parameter as in the case of traction on Granoo 0.0?
What criterion of rupture in compression I can use?
(I don't find the calibration procedure of microscopic parameters in Granoo 2.0).

Thank you,

Danh

[Cédric Hubert]

Hi Danh,

There is a kind of bonds called "PlasticBeam" 2.0, but it is perfectly plastic.
If you need linear or non Linear plasticity, feel free to derive the Beam or PlasticBeam classes to implement your own behaviour.

In the current implementation of the Beam, fracture is based on the maximal principal stress.
But you could also use fracture criteria based on the virial stress.
Take a look at the "ComputeVirialStress" plugin, in conjunction with the "ApplyBrittleFracture" plugin.
This is an ongoing work; it is not well documented and may contain bugs or errors.

Concerning the calibration of microscopic parameters, in new plugin was introduced in 2.0.
It is called "SetElasticProperty", and allows to automatically compute the microscopic parameters from the macroscopic ones. This is also experimental, and even if, to my knowledge, no bugs were reported, check that the automatically determined parameters gives the expected results on a simple test, such as tensile or bending.

Best regards,
Cédric

[LE Ba Danh]

Thank Cédric,

Danh