Destruction Values Standards and Uniformity

[Firestorm808]

Standards

I was going over the destruction value table on our calculations page, and I started wondering how we got our current values. We should probably have a page showing the process when dealing with materials not listed on our site.

Taking concrete as an example, I found the following link.

Fragmentation = Shear Strength = 60% of the Ultimate Tensile Strength

Violent Fragmentation = High-End of Shear strength to Low-End Compressive Strength

Pulverization = High-End Compressive Strength

The link doesn't elaborate on the math done. So I did it myself.

The Concrete Properties page used says the following:

Compressive strength: 20 - 40 MPa (3000 - 6000 psi)

Shear strength: 6 - 17 MPa

Conversion:

Low End Shear = 6 MPa = 6*10^6 N/m^2

1 Joule = 1 Newton * 1 Meter

1 Joule / 1 Meter = 1 Newton

6*10^6 Newtons = 6*10^6 J / Meter

6*10^6 J / Meter / Meter^2 = 6*10^6 J / Meter^3 = 6 J/cm^3 = Fragmentation

Violent Fragmentation = 17 - 20 J/cm^2

Pulverization = 40 J/cm^3

Uniformity

Regarding uniformity, is there an established resource to get our various material values because there is variance across different sites?

 

[KLOL506]

Yeah, that's about right. Low-end shear strength for frag, high-end shear strength to low-end compressive strength for v. frag, and high-end compressive strength for pulv. And we usually use 60% of tensile strength to find shear strength for most our stuff that isn't steel/iron/aluminium.

BTW, metals have slightly-different ways to figure out shear values as seen here.

As for uniformity, we just have to rely on the reliable research journals that seem to possess such an extensive list, since not every single item in the world is gonna be put into one single page: One journal may be for rocks, another for metals and another for other random materials like plastic, ceramic, etcetera.

BTW, this is not the only link we have for our values. Spino made a blog using a list for various other materials which gave us newer materials to work with. It's linked on the Calculation page.

 

[Firestorm808]

I question using compressive strength for pulverization since compression tests online best match as Violent Fragmentation.



Pulverization: Applied when the matter that was destroyed was turned to dust. We usually use this value when we see no remains of the matter that was destroyed in the aftermath of the attack.

Being reduced to dust seems way out of the compressive strength range.

 

[KLOL506]

I question using compressive strength for pulverization since compression tests online best match as Violent Fragmentation.



Pulverization: Applied when the matter that was destroyed was turned to dust. We usually use this value when we see no remains of the matter that was destroyed in the aftermath of the attack.

Being reduced to dust seems way out of the compressive strength range.

Yeah, generally that'd be covered by the Kuz-ram model or the powder-factor model.

Problem is, that only works for rock and doesn't work for either metal or wood (As in, we couldn't use it in the same blanket model as we do our current method). That's why we couldn't use it. We had a thread regarding it already a few months back and eventually concluded with it being unusable due to the above reasonings, even have a rule for it in the Calculations page now (Here's the thread if you're interested). Plus, this has multiple rock factor values to account for and last I remember, I was told by a former mining industry worker who was here on this group once (ChemistKyle) that the rock mining industry don't use blasting to turn rocks into dust-like particles, they also use crushers to make it qualify past a screening test. But if it were to be used assuming it used typical blasting values, it'd give you insanely higher results than what compressive strength could feasibly muster. I've seen some small volume results peek into high-end Tier 8 to low-end Tier 7.