[TowerTalk] Fwd: Fwd: Tower foundation and bedrock

[k7lxc at aol.com]

>  I made a lot of simulations for various wind conditions and found out that my tower, unguyed, was going to safe sustain wind up to 85 mph with a surface area of 20 sqft. As the wind, frequently, reaches that value where I live, on a hilltop in Southern Vermont, I simulated the possibility of adding guy wires. That increased the safe sustained value to 135 mph. So, against all advice, I have a guyed tower that can be unguyed.

    I don't have a problem with guying a self-supporting tower IF the guys have very little tension on them (less than 40 or so pounds). Tower strength comes from the legs - the more tension you put on the guy wires, the more compression you put on the legs thus decreasing the capacity of the legs to support the tower. With a small amount of tension, you're not trying to hold up the tower - just restrain it from wind forces. With little or no tension, you could be subject to wind slamming - a violent and potentially fatal condition.

    What is a guyed tower that can be unguyed per your comments above? I'm not sure what that means.

>  I don't know where this misnomer comes from that a self-supported should be weaker if you added guy wires. Maybe somebody can tell me. I understand if the guy wires have a very steep angle the load on the tower will increase but that is not the case with mine.
    It's not weaker - it just has potentially less capacity.

Cheers,Steve     K7LXCTOWER TECH -Professional tower services for amateur and commercial