Vertical pressure under conical stockpile
Vertical pressure under conical stockpile
(OP)
Does anyone know how to calculate the vertical pressure under a conical stockpile?
I believe it should be somewhere between the average; density * 1/3 height; and the "hydrostatic" value; density * height.
I believe it should be somewhere between the average; density * 1/3 height; and the "hydrostatic" value; density * height.






RE: Vertical pressure under conical stockpile
I ran a simple conical model and it gave the maximum internal pressure of k x max height x specific weight where k = 0.67 for a slope of 35°, and k = 0.58 for a slope of 45°.
RE: Vertical pressure under conical stockpile
The MEAN vertical pressure on a horizontal plane is given by:
Pvi = gamma * z (kPa)
Where gamma is the unit weight of the bulk material
(NOTE: Unit WEIGHT in kN/m3 NOT bulk DENSITY in kg/m3!!)
And z is measured vertically down from the centroid of the cone (i.e. use H/3 where H is the height of the cone)
The variation of vertical pressure distribution across the base is given by:
Pvix = 1.25 * Pvi * (1 – 1.6 * (x / Dc) ^ 2)) (kPa)
Where x is radial coordinate (metres) and Dc is the container diameter (metres) (i.e. use base diameter of the cone)
Therefore, the maximum pressure at the centre of the base of the pile (x = 0)is:
Pvix max = 1.25 * (gamma * H / 3)
= 0.417 * gamma * H (kPa)
And the minimum effective vertical pressure at the toe of the pile (x = Dc / 2) is:
Pvix min = 1.25 * (gamma * H / 3) * (1 – 1.6 * 0.5 ^ 2)
= 0.25 * gamma * H (kPa)
Vertical pressure variation is parabolic across the radius.
Hope this helps!
RE: Vertical pressure under conical stockpile
RE: Vertical pressure under conical stockpile
I am aware of AS3774 but think it might not be appropriate in this situation.
I will try to find "Elastic Solutions for Soil and Rock Mechanics", by H. G. Poulos, E. H. Davis, although Amazon lists it as being out of print.
I have also read that there can be a pressure dip at the center with resulting rise of pressure at some radial distance. Under a stockpile pressures can vary as material is drawn off by reclaim from a tunnel under the stockpile.
RE: Vertical pressure under conical stockpile
RE: Vertical pressure under conical stockpile
Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.
RE: Vertical pressure under conical stockpile
Thanks for your input...
RE: Vertical pressure under conical stockpile
RE: Vertical pressure under conical stockpile
Bear in mind that this is a preliminary result and further research might modify the result.
What can be said is that a stockpile is definately not a static, isotropic, linear elastic structure.