compaction to achieve a bearing pressure of 70KN/M2
compaction to achieve a bearing pressure of 70KN/M2
(OP)
The uderneath concrete slab is to be treated to have a bearing pressure of 70KN/M2. The organic soil has been removed and replaced with broken stones with lots of fines. This was compacted using a roller. The ground is further required to be raised by 200mm to get to he formation level to receive the concrete slab.
What type of stone and roller/compactive effort are required to achieve the 70KN/M2.
Thanks
Yamen
What type of stone and roller/compactive effort are required to achieve the 70KN/M2.
Thanks
Yamen





RE: compaction to achieve a bearing pressure of 70KN/M2
Presuming of course, that you have "good" soil exposed (and it is to depth) after removing the organics, one usually would compact the underside fill to something like 95% modified Proctor dry density (I like to use modified when I have load bearing - footings, slabs, etc.)
To gain an appreciation of how little 70 kPa bearing is - take a look at a chart of SPT-"N" value vs large 'footing'. Divide by 5, say to keep "settlement" to 5mm or so - and you will see that the "N" value would only need to be 20 or so - and this would be achievable under compaction noted above (and, I do realize this is for "extensive" depth - but to gain the appreciation it is an analogy that can be studied).