"Marcus Fox" wrote in message
...
I am trying to calculate a formula to determine approximately how much
earth/material I would need to create a "pile"  for want of a better word 
of a given height I could use just earth, but I could also have a pile of
rocks covered by earth.
The pile will be approximately cone shaped, and I know the formula to
calculate the volume of a cone. 1/3 pi r2 (base radius) x height. However,
since the soil will spread out and the base gets wider as the height
increases, I need to know to what degree this will happen, for example what
is the smallest slope in degrees where the pile will remain stable? 45? If
this is the case then the radius of the base will be the same as the height.
Thanks for any input.
Marcus
If the pile needs to be stable, you could perhaps make a 'cone' from something
like chicken wire as a frame?
Jenny
