Fallen tower
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Mylan
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It looks like they really lucked out though....
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Looks like scrap metal now... its a shame.
was that from a downburst or tornado?
Far Bloody Out! that was lucky that it stayed clear of the building!!
Mylan
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I was seriously considering a tower somewhat similar to that for my place here but that picture is giving me some serious second thoughts... Between ice, wind, and lightning I don't know if that would be wise move....
While you can't tell for certain from a photo, that appears to be similar to the Rohn BX or HBX. These are intended to be self-supporting towers (no guy wires). The legs and cross-braces are made of rolled sheet steel and the braces are riveted to the legs. In other words, they are pretty weak towers to start with and they won't handle much wind load. You see a lot of them supporting vertical antennas at fire houses and small businesses because they are inexpensive.
Good quesion
You read my mind. What was on top? Was it all verticals? Was there a couple of directionals hanging off the side? Inquiring minds wanna know.
You read my mind. What was on top? Was it all verticals? Was there a couple of directionals hanging off the side? Inquiring minds wanna know.
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judging from the photos, that tower looks to be manufactured somewhat poorly. It did not just bend over due to the wind forces, it appears to have stressed, relaxed and twisted under wind pressure. The cross brace design would have stood up better, if made of a more premium material, and held together with true bolts or welds, as apposed to just pop rivets. Maybe they chose this model tower due to the low cost. Another reason they may have chosen this lightwieght tower, was because they probably only wanted the hieght for mounting maybe one specific vertical style antenna with hardly any wieght of its own, and thought this tower would support such a light antenna. It appears to be a rural fire station afterall, and they most likely did not load it up with multiple antennas. I was surprised to see NO fencing around the base of the tower to prevent kids from attempting to climb the darn thing. In the end, a better rated, rigid tower would have saved them money and heartaches in the future. I guess ya get what ya pay for. Glad no one was hurt.
Yeah, by the looks of it that was a piece of crap from the git go and it doesn't look all that old either. You get what you pay for, maybe next time they'll buy quality.
If by "pop rivets" you are talking about the hollow, small diameter, soft material rivets that you set with a hand tool, I don't believe that's what Rohn uses on their BX or HBX towers. From my recollection, the rivets Rohn uses are 1/4 or 3/8" in diameter and are cold set with a hammer and anvil, though they probably have an automated tool they use in the factory.
There's nothing wrong with a riveted joint. Rivets make for just as good of a joint as threaded fasteners, maybe better because you don't have to worry about losing the clamping force like you do with a threaded fastener. Next time you drive under an older steel bridge, look at what's holding it together.
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Next time you drive under a NEW steel bridge look what's holding it together, threaded fasteners. (;->)
K
kb0nly
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There is nothing wrong with the Rohn BX series, and this TOWER IS NOT A ROHN BX...
How do i know? A quick look at the photo. Notice that it tapers from top to bottom evenly without any steps in size. A Rohn/Shelby BX series tower has a size reduction at the top of each 8ft section, this one in the picture does not and the sides are flat all the way up.
Thats one of those cheapo towers that you see these wireless cable and internet companies using. They had two of them fail near me last year, went out and looked at the carnage firsthand. You might as well put up something made of cardboard toilet paper tubes as it would be stronger than that one.
They have a thinner gauge metal then the Rohn BX, compared to my two BX towers they are way too lightweight for me. If they had more than one antenna on that tower it was probably too much for it. The guy with the wireless internet company here said they are only rated for 2-3 sq ft of antenna wind resistance and their small barbecue grill like dish on the top was acting like a sail and stressing the tower.
Funny thing is they replaced both of them with Rohn/Shelby BX-64's and they are still in the air. I might still have some pictures of those towers crumpled over will have to look.
How do i know? A quick look at the photo. Notice that it tapers from top to bottom evenly without any steps in size. A Rohn/Shelby BX series tower has a size reduction at the top of each 8ft section, this one in the picture does not and the sides are flat all the way up.
Thats one of those cheapo towers that you see these wireless cable and internet companies using. They had two of them fail near me last year, went out and looked at the carnage firsthand. You might as well put up something made of cardboard toilet paper tubes as it would be stronger than that one.
They have a thinner gauge metal then the Rohn BX, compared to my two BX towers they are way too lightweight for me. If they had more than one antenna on that tower it was probably too much for it. The guy with the wireless internet company here said they are only rated for 2-3 sq ft of antenna wind resistance and their small barbecue grill like dish on the top was acting like a sail and stressing the tower.
Funny thing is they replaced both of them with Rohn/Shelby BX-64's and they are still in the air. I might still have some pictures of those towers crumpled over will have to look.
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