[TowerTalk] Concrete Anchors

[Jim Lux]

On 8/14/15 6:54 AM, Russ Dearmore via TowerTalk wrote:
> Andre,  I would avoid using anchors as the bolts are much more reliable and stronger.  If they were even remotely adequate I'm sure the tower companies would recommend them but instead they go with long anchor bolts.  An adapter plate would be pretty easy to make (or have made) and the peace of mind would be well worth it.  Good luck and 73's....   Russ  K5ZZR   My Heroes Wear Combat Boots!

Chemical anchors are typically stronger than the underlying concrete 
(that is, if it fails, it pulls out a cone of concrete with the anchor)

Tower companies recommend what's easy, and people were casting long 
bolts into concrete for decades before chemical anchors were invented.

Chemical anchors require drilling a hole, cleaning the hole, then 
installing the anchor. They're the ideal solution where you're not sure 
where the anchors need to be, or when doing retrofits.

Put your mind in the place of a tower company selling to hams, most of 
whom will do ONE foundation and tower in their life.  long bolt cast 
into concrete is easy, there are pictures in the handbook, their Elmer, 
who put up a tower 30 years earlier probably did it that way, etc.
It's the "low hassle" way of doing things.

But when it comes to "build adapter" or "install chemical anchor" it 
really depends on the individual situation, and what kind of tools and 
facilities you have.  Some people have slabs of 1/2" steel and a big 
drill/plasma cutter/welding equipment available.  Others don't.