Bending Moment of a Cylindrical Tower

Why do you have to calculate this ! Why not somebody with the skillz required ?

Reference values for intensity of wind pressure in Newton per square meter under light conditions is 1270, under medium conditions 1910, under heavy conditions 2550; for a height upto 30 meters.

The bending moment is F*d where F is the wind force on the cylinder and d is the vertical distance from the centroid of the force to the point where you wish to find the moment.

Design of the support structure is a specialized job which requires the services of someone familiar with structural principles. Please do not try it on your own.

Thank you.

Also, does the weight of the cylinder affect the bending moment? if yes, how?

I mean does the static load( i.e mass of cylinder) will have any affect on the bending moment?

The weight of the cylinder does not affect the bending moment (or overturning moment, M_OT) but it does help to resist it. If W is the weight of the cylinder, T is the tension in one of the two windward legs and x is the center to center distance between legs , the resisting moment M_R is:

M_R = W*x/2 + 2T*x

To prevent overturning, M_R must exceed M_OT by a safety factor (usually 2.0) so:

M_R = 2*M_OT.

Let me modify my earlier answer.

The weight of the cylinder does affect the net moment. The net moment is F*d - W*x/2. This is the moment applied at the base of the four legs as a result of wind and dead load combined.

Any Good ?

http://www.google.co.uk/search?q=wind+loading+and+bending+moments&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&rlz=1I7GZEU_en&redir_esc=&ei=XDF9TOTcA8mm4Ab5kbyjBg

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