Helical Anchors Used to Support Pools
For use in pools, helical anchors, when compared to either drilled piers or driven
piles, not only greatly reduce cost, but are also superior in terms of performance.
For example, every anchor installed is 1) observed by a geotechnical engineer, and
2) monitored to ensure load-bearing capacity is attained -- tasks never done with
drilled piers and/or driven piles. These practices are just some of the reasons
we've never, ever, had a reported failure in 20 years and thousands of anchors installed.
(Click here to see a two-page write up of our helical anchors in a large
pool, and the cost comparison to the drilled piers the contractor was going to use.)
(Then, click here to see a photo sequence of the installation. Note the ease
of installation, lack of off haul, and fact the entire install took 5 hours, and
compare that to drilling holes for concrete piers, off-hauling yards of soils, installing
rebar cages, capping and uncapping the holes before the concrete pour to prevent
accidents, and taking 2 - 3 days to do it. We vote for the anchors every time .
Some common questions center on the connection between our helical anchors and the
pool. In short, it can be any design. Over the past 15 years, we've installed tens
of thousands of anchors, and connected to the eventual structure with dozens of
Another question often asked is if it's possible to use anchors for a pool in a
location over the edge of a slope. The answer is yes, as we have installed anchors
to support structures on some wicked slopes. In particular, we installed anchors
to support the necessary loading of multiple structures on a 2:1 slope in Costa
Rica, terrain we can tell you was difficult for even the locals to struggle up!
This particular area was also subject to significant seismic activity, so the anchors
are indeed a 'proven and reliable solution.'
In addition, we've installed anchors for pools where the owner was worried about
the structure coming down the hill. The anchors were installed in a 'battered' (diagonal)
arrangement to resist downhill movement, and have had zero movement. Again, whether
it's a pool, home, commercial building or solar tower, anchors are commonly utilized
in areas of slope and/or creeping movement.
Finally, the single most asked question we're asked is in terms of the corrosive
aspects of installing steel pipe in the ground. In fact, and over the past 100 years
steel anchors have been used, the industry has done mountains of study on this issue
and produced volumes of information. In general, steel does not corrode a few feet
under the ground, as there is no air to act as an agent. So, and most of the time,
it's only the top few feet that are of concern. And, although every soil has various
corrosive attributes, most can be solved by applying a protective layer to the steel,
such as an epoxy coating, a galvanized coating, and in the absolute extreme cases,
an electrical current.
For every installation, our standard practice is to design to the spec provided
by a registered corrosion engineer (and, we have one of the world's top on our Advisory
Board, Ms. Kerrie Howell). In addition, we have done a ton of research and study
re the corrosion issue, and published a White Paper on the subject, 'Corrosion of
Helical Anchors in Soil' (you can click here to read it). You'll see the maximum
expected loss of less than 2 mm of steel is 75 years. The length of time required
to experience 3.2 mm (1/8 in.) metal loss is often defined as the service life;
at this rate, the useful life of anchors could be expected to exceed 125 years.
Second, visuals are good, so we have attached both an engineering schematic of the
LFRD, as well as a five-picture sequence of an installation over an anchor. Note
ease of install, and how the device does not inhibit any connection that would go
from the ground up.
Third, the LFRD is very cost effect -- especially when compared to a concrete collar
-- and is vastly easier to install than any other lateral solution.
If you have any questions about our helical anchor solutions for pools, or are already
sold and want to get an installation under way, call us at 925.683.2739.