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Column Buckling Due to Unifoemly Distributed Load

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Fellow engineers,
 
        I am working on two free-standing stacks.  A question has come up regarding maximum permissible slenderness ratio, KL/r.  AISC, CISC, and other structural codes traditionally limit KL/r to being less than 200.  ASME SST-1-2000 doesn't cover the subject.  For KL/r AISC permits stress of 3.73 ksi whereas a stack axial stress will be about 10% of this value.
 
        I submit that limiting KL/r to a maximum of 200 is much too conservative since the loading assumptions for AISC and others are not applicable to stacks.  Structural load cases assume ALL loading in the form of a point load at the top and NO uniformly distributed load while stacks have NO point load at the top and ALL of the load is distributed along the height.  Guyed stacks are a different matter, of course, because most of the load comes from the force of the guys or from the weight of other sections of the stack above the guys; I would always restrict KL/r to being less than 200 got guyed stacks.
 
        My thought was to solve the Euler equation and use a safety factor of 2.5 or 3 but my skill with differential equations is not what it used to be.  The equation I am trying to solve for UDL only is
 
EI(d2y/dx^2) = -M
 
where
 
M= m* Integral (from x to L) of w*y*dx
 
M = bending moment
w = weight/foot
 
 
        Any other thoughts, references, or help in solving the equation would be welcome.  Also, since I'm never sure if I'm connected to the list or not any more, a direct response would also be welcome.
 
Thanks in advance.
 
H. Daryl Richardson