"Toy" wrote in message ...
"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



first it depends on the material.

sand would have a shallower base angle for instance.

if you have the same amount of material and it starts to spread out, without
adding more material, the volume remains the same.

or am I missing something here.




======================


http://grapevine.abe.msstate.edu/~ft.../vol/cone.html

put in your sizes and hey presto, volume....