Absolutely the WORST possible way to build a guyed tower is to set the
bottom section in concrete. It is far better to use a base plate with a
pier pin in the concrete, to allow the tower base some freedom of movement
in heavy winds. The tower will tend to sway and twist in windstorms, but if
the base is set in concrete, that puts an unnecessary amount of stress and
shear on the tower structure.
Another problem is that it is nearly impossible to get the buried base
section absolutely plumb, no matter how carefully you measure. And
concrete foundations do settle with the passing of time, so with certain
soils, the tower may not stay plumb even if it was achieved initially.
You very rarely see commercial tower installations built that way.
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