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.
You can get a pretty good approximation using one of the charts out of Poulos' book on elastic methods. As I recall, it has several charts for a circular loaded area - treat the conical load as a stack of "hockey pucks" with a steadily reducing diameter. Since the analysis is elastic, you can simply superimpose the results -
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