Fracture energy in masonry

[Sadegh]

Hello,

I am writing to inquire about the equation of fracture energy using ASDCONCRETE3D. As presented in one of the videos in youtube(https://www.youtube.com/watch?v=dmUjbazC5js) from ASDEA channel the Gt and Gc is calculated as below:
Gt=0.073.fc^0.18
Gc=250.gt
Could you please let me know how is this developed or any resource article to find out more about this equation?

Thank you,

[kesavapraba]

Hi, By default, the fracture energy calculation is referred to FIB model code. https://www.fib-international.org/publi ... codes.html

[Sadegh]

Thank you for your reply, I have found the formula for Gt, but I have not found for Gc=250.Gt which is referred in the webinar. Could you please let me know the exact reference for this one, so I can find out more about it. As far as I searched, I didn't find it in the reference you kindly mentioned.

Thank you,

[STKO Team]

Typically codes give formulas for tensile fracture energy only (like the one from model code).
Compressive fracture energy is more aleatory.
If you assume that the compressive uniaxial behavior has the same shape of the tensile behavior but just scaled, then the fracture energy will be roughly 100 times larger than the tensile one , because fc/ft is typically 10, so you scale 10 times the stress and 10 times the strain (so 10*10 will be the scale factor for the area).
However the compressive behavior is typically more ductile than the tensile one, thus the scale factor 250>100.
Anyway, it's a value calibrated on some experimental tests on normal strength concrete. If you want a more correct value for a specific test, you need to integrate the area under your experimental compressive behavior

[Sadegh]

Sorry, isn't this formulas for concrete wall? are these applicable for masonry walls too?

Thanks,

[STKO Team]

Well our presets are for concrete, if you plan to use it for masorny or other materials you should get the fracture energies from experimental tests.