User Forum of Software BASEMENT

Alyssa

User

From: Aix-en-Provence, France

Registered: 2019-10-28

Posts: 41

How to define "medium" diameter for grain class

Hi

I found this in the manual for getting the proper diameter that represents the grain class (under 3.2.4.3):
Each grain class is defined by its medium diameter and has a percentage.

Is this then the median? If my first grain class is between 1mm and 8 mm, is the representative D= 4.5 mm?

So you are not using characteristic grain size diameter for a grain class as stated in Gary Parkers e-book?:
Di= (Dbi*Dbi+1)^0.5

I just want to make sure I am using the right one. I was using the last one, but I guess this is wrong for Basement?

Thanks

Alyssa

Matteo Facchini

Developer

From: Trento

Registered: 2014-09-05

Posts: 281

Re: How to define "medium" diameter for grain class

Hi Alyssa,
the discretization of the grain size distribution is up to you, basement just performs the calculations with whatever sizes-fractions you give it as input.
I would recommend however to discretize your GSD using what parker defines with the greek letter "psi", i.e. the base-2 log of each diameter, to calculate the size relative to each class. To answer your question: use what parker suggests, that's also, I believe, what is inended in the manual
Best

Alyssa

User

From: Aix-en-Provence, France

Registered: 2019-10-28

Posts: 41

Re: How to define "medium" diameter for grain class

OK, good to know. Thanks!