When installing free standing towers on ROCK, you have a few options. My
buddy has a huge trylon, that is located on solid rock.
Instead of messing about with jack hammers, he used TRYLON'S suggested
method and used rock anchor bolts.
Three holes were drilled into the rock, about 2" diam x XXX feet deep.
Anchor's inserted and packed with special epoxy goop
[ NON shrinkable epoxy] On some trylon towers, 2 x anchor rods are used
for each tower leg [ 6 x anchor's in total.. and 5' long]
We also used the same technique at the Telco I worked at for 34 yrs... for
microwave tower's and also cell towers... located on remote
mountain tops [ read 100++ mph winds + 1-3" of radial ice] Rock anchors
also used [ usually in pair's] for guy anchors, for guyed microwave
Plan B [ also from Trylon] is to use huge jumbo size HILTI anchors.
These things are are 24" long x 2" diam ... and made spec
for anchoring towers ! I have installed thousands of hilti anchor's at
work, yr ago.. and usually in both floors and also hundreds of em
in the concrete ceiling's [+ elevator shafts etc] We hung thousands of
lbs of cable runways on small hilti anchors, suspended from the ceilings.
These day's everything has to be seismic rated in BC. In the last few years,
all our equipment bays [19"-30" wide] are heavy duty steel
with these monster size hilti's in the floor. When that earthquake in wash
state hit us.. a few yrs ago.... they held just fine... didn't budge.
Didn't even know they made these super jumbo size ones for tower's. The
internal bolts for em are 1" diam x 30" long. The anchor itself
is 2" diam x 24" long... and requires a special hilti drill. These 2"
x 24" long hilti's I believe, are made for CONCRETE... dunno if they can also
be used in
rock..or not. The idea of em is so an existing concrete base can be
re-used on another tower. All this info is on Trylon's site.. or just phone
later....... Jim VE7RF
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