Relating Undrained Shear Strength to non-engineers

[JTRdirt]

Hi all,

I'm trying to come up with some examples of every day materials which I can use to describe the stiffness/undrained shear strength of mine tailings to a non-engineering audience. The specific case deals with mine tailings which range between approx. 100 and 800 psf undrained shear strength.

Its easy to say "oh that's as soft as toothpaste", but I really would rather have something to back me up when I say that.

thanks

 

[BigH]

For 100 psf (5 kPa), try "loon shit" - a non-technical term for the ooze on the bottom of a lake. 800psf (40kPa) is considerably stiffer . . . - why not give the rough field guide about thumb imprint . . . see: Table 3.5 in

http://www.udot.utah.gov/main/uconowner.gf?n=200610120954411

 

[JTRdirt]

Thanks for the reply BigH

I had actually begun with a similar table, but wanted to take it a step further to take out the process of people having to think "what types of things are readily dented with strong pressure of my thumb". I came up with this table with a little brainstorming help from my co-workers (this would append to a table similar to the table you pointed out above.

Very Soft Toothpaste, Mashed Potatoes, Jello

Soft Play-doh

Medium Stiff Stick of butter right from fridge, silly putty

Stiff Tub of ice cream

Very Stiff Fully inflated basketball, unopened bottle of soda

Hard Hard candy, ice cube

 

[BigH]

Tub of ice cream . . . depends on the temperature at which it was stored, I have had some where I had to cut it with a knife just to be able to get a scoop in - that I would hesitate to say very stiff . . .

 

[Bob83]

Thanks......

 

[JTRdirt]

tub of ice cream was the last one I had... couldn't think of anything else that would work