nunya
SEE ROCK CITY 475 MILES
Premium,MVM
join:2000-12-23
O Fallon, MO
clubs:
 ·AT&T CallVantage
| reply to UHF
Re: Digging a hole in limestone
I'd core the limestone and see how big of a shelf you are working with. FWIW, I've seen large buildings and towers supported on limestone ledge.
If its more than a few feet thick, I would call the tower manufacturer and verify windloading and supporting on a limestone shelf. You need to rent a coredrill on a stand. They can be wheeled in.
If you can core down 5-6 feet and still be in substantial rock, I'd fill the core hole with grout and rebar. That's assuming this is a small self supporter. If it's a monopole or guyed setup, you're on your own.
For larger towers, it takes professionals with professional equipment to get it done. Not much of a way around that.
--
Looks like Reverend Wright got his wish - God Damn America. |
|
UHF
All static, all day, Forever
Premium,MVM
join:2002-05-24
clubs:
 ·Qwest.net
·Callcentric
 ·surpasshosting
 ·Dish Network
·Future Nine Corpor..
| Rumor is they used dynamite when building the houses here. We're roughly 1/4 mile away from a limestone quarry, so I'm guessing the limestone goes down a good 60+ feet at a minimum.
In order to build the tower here the city requires the foundation to be concrete, 4' down. So I'm stuck with that. I'll have to just keep chipping away it at. I'm making progress, but it's slow, and a lot more work than I'd like it to be. |
|
nunya
SEE ROCK CITY 475 MILES
Premium,MVM
join:2000-12-23
O Fallon, MO
clubs:
·AT&T CallVantage
| reply to UHF
I'd be willing to bet you could get a variance with engineered drawings. Hiring an engineer may be cheaper and easier than proceeding with an unnecessary footing dig.
--
Looks like Reverend Wright got his wish - God Damn America. |
|
UHF
All static, all day, Forever
Premium,MVM
join:2002-05-24
clubs:
·Qwest.net
·Callcentric
·surpasshosting
·Dish Network
·Future Nine Corpor..
| reply to UHF
Well, the concrete is free, so the only cost to the footing is digging the hole. The limestone is somewhat shale-like, in that it breaks off fairly easily into little slabs. I would not trust a heavily loaded ham radio tower anchored directly into this as I would be worried that it would fracture too easily, and the hole is bordered on one side by back-fill from when the house was built (house bracketed tower). This rock is certainly softer than concrete.
I stopped at the local rental store this morning, the owner thinks a jack hammer is the way to go. That's what he used when he dug the foundation for his garage and his mini-hoe couldn't break through the limestone. |
|
UHF
All static, all day, Forever
Premium,MVM
join:2002-05-24
clubs:
·Qwest.net
·Callcentric
·surpasshosting
·Dish Network
·Future Nine Corpor..
| reply to UHF
I made pretty good progress tonight. I had a couple inches worth that was super hard, but finally broke off into large pieces. Under that it's getting softer. Which is good, and bad. Bad because it fragments into smaller pieces, good because it fragments a little easier.
Still going at it by hand, and I'm at least a third of the way now. My wife is pretty much ordering me to dig by hand, she says if I want to construct an ugly ham radio tower I'm going to have to work for it. She can be a real slave driver, LOL!
Thanks for all the tips, guys! |
|
drjim
Premium,MVM
join:2000-06-13
Torrance, CA
clubs: | I suppose "ugly" is in the eye of the beholder.
Hang in there, you'll get it finished.
--
One man's Magic is another man's Engineering. |
|
hitachi369
Embrace Your Rights
Premium
join:2001-10-03
Grand Rapids, MI | reply to UHF
Where do you live? Maybe there are some members in the area that could help? |
|
UHF
All static, all day, Forever
Premium,MVM
join:2002-05-24
clubs:
·Qwest.net
·Callcentric
·surpasshosting
·Dish Network
·Future Nine Corpor..
1 edit | reply to drjim
said by drjim  :I suppose "ugly" is in the eye of the beholder. Hang in there, you'll get it finished. To me it will be a very beautiful thing! I acquired a tribander and a rotor over the weekend, so I need to kick it up a notch with the digging! |
|
