Covington Electric Cooperative
Project Description: Following a historic outbreak of tornados in Central Alabama, the Covington
Electric Cooperative decided to construct a computer vault on their property
that would withstand tornadic winds of up to 250 mph. The pre-fabricated
reinforced concrete building was designed and constructed in a factory
in Bessemer, Alabama by Modular Connections and transported to the site
in Andalusia, Alabama about 200 miles away by truck.
How was Ram Jack Involved: In order to resist the wind uplift forces, deep-seated helical piles
were needed. Alabama Ram Jack was contacted to evaluate the application.
Originally the piles were specified to be a relatively small size, 1 1/2
inches diameter. After reviewing the soils report, the engineers at Ram
Jack quickly discovered that small diameter piles would not suffice for
this site. In particular, the soils report showed that there is a relatively
stiff, sandy clay soil at depths of 6 to 8 feet which the specified smaller-diameter
piles would not be able to penetrate, and then the tension-only piles
would be vulnerable to pull-out. The Ram Jack analyses showed that our
2 7/8 inch diameter piles with a triple 8”/10”/12” helix
would be needed to penetrate the near-surface stiff soils and reach the
depths needed to attain the uplift resistance. Alabama Ram Jack was awarded
the job primarily because of their expertise in evaluating the situation
How was Ram Jack Involved - Continued: This job also posed a challenge in that the building was prefabricated
with steel plates on the bottom for welding to the helical pile brackets
that were installed in advance of the building delivery. Therefore, the
installation had to be very precise with only a few inches tolerance.
Our production crew was up to the task and the building was placed atop
the brackets and welded to them to provide the necessary uplift resistance.
The electric cooperative now has additional assurance that their operations
will not be disrupted during tornadic weather.
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