||Backfill- Compaction vs natural settlement
||10/10/1999 11:53:00 PM
I am looking for some feedback on whether it is
necessary (cost-effective) to mechanically compact
clay backfill under the foundation of my garage,
driveway, and porch aprons etc. Or can the material be
allowed to settle on its own similar to how one would
treat a sand backfill.
My builder's intent is to load in from 4 to 8 feet of
loose backfill (which consists of rather clumpy non-
expanding clay soil) into the garage foundation and
other areas and allow it to settle on its own over the
winter and then top it off prior to finishing the
garage slab, driveway etc.
The builder is very confident that this method will
not result in anything but minor cracks etc. in the
finished slab and asphalt driveway. He has indicated
that this is a standard practice in residential
construction and can point to several of his homes
constructed in the last two years that have been
constructed in a similar mannter with no obvious
problems. I would feel better if he could point to a 5
to 10 year example.
I contacted a geotechnical engineer who has
recommended that the soil be compacted. I get the
sense that my builder is thinking this should by an
extra, but i thought I would check to see just what
the Best Practices are for this sort of thing.
||Partnership for Advancing
Technology in Housing (PATH)
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