In the central New Mexico mountains
where we build, clay and other
problem soils can behave unpredictably,
expanding and contracting
excessively, or settling and shifting. Add
in an ill-timed rain or snow storm during
foundation prep work, and what
appeared to be a suitable, compactable
subsoil can suddenly become a wet,
sticky, non-compactable mess.
Unfortunately, it's sometimes difficult
to determine exactly what soil types
exist below the footing trenches. Even
proper soil investigations may not identify
all problem areas, because the
results are typically based on only a few
borings that are taken to be representative
of the site.
When excavations reveal surprise
soils with questionable loadbearing
ability, we use a technique that protects
against foundation settlement.
Simply put, it involves