Design for combined bending and compression

Last updated: February 01, 2022

As for all design codes in RAM Concrete Column, column design for EN1992 is carried out by iterating through the various bar patterns that are applied to a particular column and determining the most effective bar pattern for the given loading conditions.

Columns are designed to satisfy the provisions of clause 6.1 of the code. The following points are to be noted:

Assumptions are as given in 6.1 (2).
Columns are restricted to a maximum aspect ratio of 4. (Clause 9.5)
A parabola-rectangle stress block is used as defined in 3.1.7 (1) of the code.
Calculation of design moments is according to Equation 5.32 of the code.
Curvature of the column is calculated according to 5.8.8.3 (1) and the curvature distribution factor ‘c’ is taken as 10 (≈ π²).
The column is checked by determining the moment capacity of the column (in each direction separately) under the given axial load. The unity factor is determined according to the formula in 5.8.9 (4):
${(\frac{M_{EdX}}{M_{RdX}})}^{2} + {(\frac{M_{EdY}}{M_{RdY}})}^{2} \leq 1$

The values of M_EdX and M_EdY should include any second-order moments.