Question: how to work out how much concrete to fill a hole?
Answer: EXAMPLE: How much concrete is needed to fill 5 holes 1200mm deep and 1050mm round?
ANSWER: One hole takes 1.039 cubic metres, therefore 5 holes = 5 x 1.039 = 5.195. ( say 5.2 cubic metres)
NOTE: When the Diameter of a hole is doubled, it takes 4 times more concrete.