[TowerTalk] Tower Grounding advice

[Jim Brown]

On Tue, 7 Jul 2009 14:57:46 -0400, Bill Fikis wrote:

>And  if there is a lightning strike,  then  won't  that  strike 
>cause the concrete  to explode ???

According to the research I've seen, no. On the other hand, it's 
good to bond the rebar together to minimize the electrical stress 
and arcing in the case of a strike. AND you should have other 
electrodes in parallel with the concrete. 

Think of it this way. Concrete IS a conductor, it WILL act as an 
earth electode, and unless you've done something serious to isolate 
it, the tower base IS electrically connected to it. And both good 
engineering practice and all building codes require that all earth 
electrodes be bonded together. 

To study this, look up "Ufer" in reference texts or on the internet. 
Herbert Ufer is recognized as having pioneered the use of a 
conductor encased in concrete as a grounding electrode, and such an 
electrode is called a Ufer. 

73,

Jim K9YC