N-M interaction chart to Australian Standards 2

[Pretty Girl]

The below is the N-M interaction chart for Eurocode for a biaxial concrete column.

Do Australian standards provide any guidance to come up with the N-M interaction diagram? Which clauses I need to look at if I want to make our chart compliant with AS 3600?
I want to know the calculations which involves with this and especially the limits, caps, and other considerations to make it AS 3600 compliant.

Does it have some different way of calculating strains for pure compression and when column is not in pure compression?

How do I construct a chart which is compliant to Australian standards?

@IDS @Celt83

 

[Retrograde]

Section 10.6.2 is the relevant part of AS3600.

 

[IDS]

The interaction diagram shown is not for biaxial loading. The examples in the book find the capacities about the X and Y axes, and then combine the ratios of applied moment to moment capacity, using the code simplified approach.

The Australian code (AS 3600) has procedures for finding the moment capacity for any specified axial load, so those procedures can be used to generate an NM diagram, as for the Eurocode. The basic analysis procedure is the same as in the Eurocode, but there are significant differences in application:

1. The design ultimate capacity is calculated using the unreduced material yield stresses, and the resulting axial force and bending moment are factored down by a single factor which varies between 0.85 for tension and no axial load down to 0.65 or 0.6 for axial loads above the balance load. This is a similar procedure to that used in ACI 318, although there are differences in calculation of the intermediate values.

2. The code only gives detailed procedures for a rectangular stress block, although it specifically allows other recognised stress blocks to be used.

3. The factors for the depth and design stress of the rectangular stress block are different from the Eurocode values.

4. The specified strain at the compression face is 0.003 for all grades of concrete. This is reduced to 0.0025 for calculation of the "squash load", i.e. for sections in uniform compression.

5. The squash load is reduced by an additional factor between 0.72 and 0.85. See code extract in the previous post for details.

6. The code specifies that a straight line interpolation may be used for calculations when the NA is outside the section.

7. Sections with high axial load have detailed requirement for confinement reinforcement, and the effect of confinement on section capacity.

 

[Pretty Girl]

Thank you @IDS and @Retrograde . I'll go through those and will get back to you.