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Shape of bending moment

Shape of bending moment is expressed by ratio of first order end section bending moments without influence of imperfection in direction of the selected local axis. The ratio of these moments (value r_m) depends on type of member and on shape of shear force.

if type of member is unbraced around local axis (sway= YES), then r_m = 1,0
if type of member is braced around local axis (sway= NO) and first order moments arise only from or predominantly due to imperfections or transverse loading (maximum bending moment along the member is not at the beginning or at the end of the member ), then r_m = 1,0
otherwise, value r_m is calculated according to formula r_my(z) = M_01y(z) / M_02y(z) and |M_02y(z)| ≥ |M_01y(z)|

where

M_01y(z)	the first end bending moments around y(z) axis of LCS with lesser absolute value as second end bending moment
M_02y(z)	the second end bending moments around y(z) axis of LCS with greater absolute value as first end bending moment.
r_my(z)	the ratio of bending moment around y(z) axis of LCS which is used for calculation limit slenderness around y(z) axis of LCS

The coefficient C is than calculated according to formula

C_y(z) = 1,7 - r_my(z)

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