I feel your pain. Virtually ALL my 5 acres is
bedrock. I tried finding a place to dig out a
base for my 55 foot crank up tower, to no
avail. I went through lots of questions, trying
to figure out how to make it happen. I checked
with local engineers, TT engineers, concrete
engineers, blasting engineers, and finally
decided to just build the base on top of the rock by myself.
The soil was about 6 to 8 inches deep, then solid
rock. My decision was to get a hammer drill with
a concrete/masonry bit and drill holes in the
rock to put in the re-bar for the concrete
form. I used a special cement (Rockite) to keep
the re-bar in place, made the re-bar cage, built
a plywood form around it, then reinforced the
heck out of the frame and poured the
concrete. Dang if it didn't work. The tower has
been up for a couple of years, and has withstood
some 70 mph wind gusts. No problems at all. You
can find a bit more detail at:
Click on Ham Radio, then Tower Project. Hope
this adds a bit of encouragement. No, I didn't use an engineer.
At 04:15 PM 2/12/2006, Les Kalmus wrote:
>In a few months I will be starting construction on a new house which will be
>located on top of a hill on a adjacent piece of property. My HDX589 is
>currently installed on the manufacturer's recommended base of 5x5x8.5 feet
>of concrete with rebar.
>Test holes in the vicinity of the new house have revealed between 16 and 40
>inches of soil on top of the rock the hill is made of. A blasting contractor
>has told me that the stone is very strong and stable and he will not have
>any problems blasting for the house basement and foundation.
>I won't be able to dig another hole and use the same method as the current
>location. Instead, I have been told there are bolts or rods that can be set
>into holes drilled into the stone and epoxied in place which can support the
>I will probably need an engineer but don't know where to begin to find one
>familiar with this type of work or what alternatives exist. Anyone familiar
>with this technique or alternative method who can steer me in the right
>direction? Any particulars I need to provide to him/her that I need to
>research in advance?
>I am located between New Paltz and Kingston, NY.
>73, Les W2LK
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