Introduction

Slenderness and limit slenderness of the column should be checked before design or check of the members. Using of second order effect in calculation depends on the check of slenderness, because if the check is slenderness is greater than limit slenderness), the second order effect has to be taken into account for column calculation.

Conditions	Calculation of second order effect
λy > λlim,y or λz > λlim,z	YES
λy ≤ λlim,y or λz ≤ λlim,z	NO

The slenderness and limit slenderness is calculated according to clause 5.8.3.1 and 5.8.3.2 in EN 1992-1-1. The following preconditions are used for calculation :

• The slenderness is calculated for beams and columns and for general load (N + M_y + M_z)
• The limit slenderness is calculated only in case that axial forces is smaller than zero (N < 0 kN)
• Cross-section with one polygon and one material is taken into account in version SCIA Engineer
• The material of all reinforcement bars have to be same in SCIA Engineer