[TowerTalk] Rooftop Poles Diameter Design

[jimlux]

Eng. Osama Ewaida wrote:
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> Hi
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> What the key parameters affect the pole diameter in addition to Equipment load, Wind Load, and Wind speed ( both operational and survival)
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> The subject poles can be fallen under different mounting scenario such as : 3 meters wall mount, 6M Non-penetrating poles 
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> Is there a tool / formula can calculate and recommend the pole diameter with what sort of inputs required? 
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> Many thanks for your kind support and quick answer in advance. 
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There are a variety of spreadsheets out there that can calculate bending 
loads, and the failure loads for various tubing materials and tubing size.

For calculating the actual wind loads, it's a bit trickier, because the 
aerodynamics are nontrivial.  A decent approximation is to assume that 
the antenna is the same as a flat plate with area equal to the projected 
area of the antenna parts (that is, a 5cm diameter tube 3 meters long 
has an equivalent flat plate area of 3*.05 = .15 m^2)  You then 
calculate the aerodynamic load by 1/2*rho*v^2*area in the usual way.