[TowerTalk] Tower Base Construction Question(s)

Marinus Willemstijn willemma at telkomsa.net
Tue Dec 18 11:46:04 EST 2007

Good Day to all


I am constructing a tower base and have tried to read about the subject as
much as possible. I have a few questions which I hope can be answered via
this forum.




Tower is Triangular 3 x 7 M sections Crank Up tower tilting over at 2
meters. Soil is a solid Red Clay soil. What I could gather is that the base
should at least be 1Meter deep (Form soil level) so the hole I dug is 1M x
1,7M x 1,17M and then about 150mm of concrete will be above soil level - the
bolts used to tie down the base will be approx 100mm above the concrete.


My question is about the cage. I am using 16mm Re-Bar. I have read that the
rebar cage should be around 300mm away from the side of the Concrete block
to ensure its away from the soil at the bottom and sides. 


Is this correct?


Secondly I have read that the cage is made with binding wire or cable ties
and not welded.


Is this correct?


Now my towers' base gets tied down with 3 threaded bolts of 1 meter each


Do I weld these three bolts to the cage? If not how is it connected? I know
that somehow the 3 bolts must be electrically connected to the Rebar cage
for earthing purposes.


Lastly I see many drawings that the ends of the vertical bars of the cage
are bent - why is this and is it really necessary?


Any help or advice will be appreciated - Thanks in advance.



Marinus Willemstijn



More information about the TowerTalk mailing list