Could someone explain to me what the numbers mean on a compaction certificate they are shown as a fraction.

if it says 8/300 that means 8 blows of the falling weight per 300mm

the higher the 1st number the better as it means the ground is more compact

in addition they should have a second number for the second 300 mm, both of them should be over 8/300 to pass the standards

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I'm not here for a long time......I'm here for a good time!

Yeah it will be blows per 300mm.

Thanks but still confused. A report I have shows the following figures.
6/17 7/15 8/15 15/16 18/6 7/19 6/18 what does the bottom figure represent.

What is it for? Is it for a house pad or something else?

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Losing is worse than death. You have to live with losing....

Yes house pad. As was suggested is the 2nd number the numbers of blows for the 300 to 600mm

Looks like blows per 300mm for various locations on the house pad. Usually they are done to 1m (900mm) but refusal may be accepted as >20/300mm depending on compaction specs etc.

Might be worth finding out the calibration blows/300mm for your block/sand type.

If the fraction results (x/y) are for different locations, its most likely means x blows for 150-450mm, y blows for 450-750mm.

Should really have a PSP correlation for the particular sand. the 8 blows or more is just an estimate. eg you can have a sand that only needs 5 blows for 95% compaction, other sands may require 15 for the same level of compaction.

cheers