available second moment of area
available second moment of area
(OP)
thread794-187769: Stiffening Rings
Im just doing some calculations for stiffening rings for a cylinderical pressure vessel under external pressure. Refering to UG-29 can someone help me for the formula for finding "available moment of inertia, I" in the definition given. The stiffened ring is a rectangular cross section. if I apply bh^3/12 on this 40*8 cross section it comes out to be 1706.6mm^4 which i get a feeling is not the value used for "available moment of interia".
thanks for help
Im just doing some calculations for stiffening rings for a cylinderical pressure vessel under external pressure. Refering to UG-29 can someone help me for the formula for finding "available moment of inertia, I" in the definition given. The stiffened ring is a rectangular cross section. if I apply bh^3/12 on this 40*8 cross section it comes out to be 1706.6mm^4 which i get a feeling is not the value used for "available moment of interia".
thanks for help





RE: available second moment of area
The formula you use for moment of inertia of the flat bar about its own neutral axis is correct but is your orientation correct? If your flat bar 40x8 is oriented with the 40 mm side perpendicular to the shell plate surface (the "strong" way) then b = 8 and h = 40, giving a much greater moment of inertia.
RE: available second moment of area