D13.B.3.3 Flexural members
Members subjected to the action of bending moments and shear forces are called flexural members.
Calculation of flexural members consists of verification of strength, stability and deflection.
Normal and tangential stresses are verified by strength calculation of members. Normal stresses are calculated in the outermost section fibres. Tangential stresses are verified in the neutral axis zone of the same section. If normal stresses do not exceed design steel strength and tangential stresses do not exceed design value of steel shear strength Rsγs then according to clause 5.14 of SNiP 2.01.07.- 81* principal stresses are checked.
General stability of member subjected to bending in one plane are calculated in accordance with clause 5.15 of SNiP 2.01.07.- 81*, and subjected to bending in two planes – in accordance with Guide to design of steel structures (to SNiP 2.01.07.- 81*). Coefficient φb value is determined according to appendix 7 of SNiP 2.01.07.- 81*. Additional data about load (concentrated or distributed), numbers of bracing restrains of compression flanges, location of applied load are required. For closed sections it is assumed that coefficient φb= 1.0.
Simply supported (non-continuous) beams can be calculated in elastic as well as in elastic-plastic state according to requirements of clause 5.18 of SNiP 2.01.07.- 81*. Calculation can be selected by specification of structure in input data.
Stiffness of flexural members is verified comparing input value of deflection limit (through parameter DFF) with maximum displacement of a section of flexural member allowing for load reliability coefficient, which is specified, in input data. Limit values of deflection are determined in accordance with SNiP 2.01.07.- 85 Loads and Actions. Addition chapter 10. Deflections and displacements. Verification of deflection is performed only in the case of review (CHECK) problem.