NIEUWE BLIK OP KIP EN KNIK - Bouwen met Staal

H 1a Summary
The 2 nd order factor
All necessary data concerning load, eccentricity and factors, depending on load case and bar
properties, are covered by the general formula:
1 1 1
= +
n n n
* * *
z M F
Herein:
( ) 2
kM 1 1
1 y
=
n M + k M eF
* 2
M kr 2 y1 Ez
1 Fc
=
n F
*
F Ez
reflects the influence of the bending moments,
reflects the influence of the compressive normal force.
The definitions for these terms and constants are included in the list of notations in Chapter 3
and justified during the derivation of the formulas in Chapter 5.
The factors k 1 and k 2 are dependent on the combination of beam-column type and load case.
In Chapter 6 the same formula is derived using a method based on the principle of strain
energy; this yields the same values as were found in Chapter 5.
Beam-columns with a lateral support are considered in Chapter 7. This requires adapted
formulas for n z*. In Appendix 7 some special topics, for instance consequences of elastic
lateral supports, are discussed.
Displacements and moments of 2 nd order
With help of n z* and the applicable initial displacement v0 (which may be adopted from the
relevant design codes) the 2 nd order displacements are determined in Chapter 8 using:
1
v = v
2 * 0
nz
−1
The relationship between the 2 nd order moment in the 'weak' direction and the displacement
may be written as:
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