how to calculate the defference in between loose stock volume and natural exacavated volume of rock.?

Question

we excavated the mountain and stockpiled according to classification of material and measured the original excavation cross sections without classifying the material.now the conflict is that how much we did common excavation and rock excavation,as per practical conditions we couldnot able to have elevations of common and rock strata,and for payment now we need to calculate the percentage of common and rock excavation,with the help of measuring volumes of stockpiles,i want to know the percentage difference in between the loose stockpile volume and original excavated volume ,by any calculation method or thumb rule etc,whatever it may be to come to conclusion to know th edefference in between them.

Answer 1

What you are looking for are bulking factors.
The second figure in each line below refers to the rough bulking factor for each rock type.
eg chalk = 1.50, granite = 1.72

you could use 1.5 as a rough average. That is after excavating a volume of rock, its volume will expand to about 1.5 times its original volume in the ground.

Chalk 1.85 1.50 0.97 E
Shales 2.35 1.50 1.33 M-H
Limestone 2.60 1.63 1.36 M-H
Sandstone (Porous) 2.50 1.60 - M
Sandstone (cemented) 2.65 1.61 1.34 M-H
Basalt 2.95 1.64 1.36 H
Granite 2.41 1.72 1.33 H