Does characteristic yield strength of steel reinforcement (fyk) and Youngs modulus affect buckling?

[bojoka4052]

According to Eurocode 2, the characteristic yield strength of steel reinforcement (fyk) should be within the range from 400 MPA to 600 MPA. I believe the Young Modulus is usually around 200 GPa for steel.

Does these two material properties affect the buckling of a column subjected to a compressive load?

 

[HTURKAK]

If you assume the steel is perfect material , you can use the famous Euler's buckling formula.. But a reduction is applied for imperfections which is somehow proportional with fyk.

The following doc. with worked examples is useful to get the buckling concept of EUROCODE 3

https://eurocodes.jrc.ec.europa.eu/...ations/05_Eurocodes_Steel_Workshop_SIMOES.pdf

 

[Ng2020]

Yes.

Whilst there are numerous formulations for various buckling modes of different structural elements, they are generally related to the simple Euler column formula, for which elastic modulus is an input.

For short column lengths with stable cross sections, in my discipline compressive yield strength is usually considered to be the cutoff.

More simply: A column made of rubber will buckle at a much lower load than one of the same dimensions but made of steel.

 

[centondollar]

This is taught in your basic structural mechanics classes. Elastic modulus (which may be depend on direction or location inside the structure, for e.g., laminates or sandwich structures), stiffness (e.g., bending stiffness of plates and beams), length (or ratios of side lengths for plates) and boundary conditions are the primary characteristics that determine buckling capacity.

Regarding the relationship between buckling and yield strength that you may find in some standards, take note of the following: the eigenvalue (classical) buckling problem provides you with a buckling multiplier that does not include the effects of imperfections. The standards provide you with a means to input the aforementioned buckling load and additional parameters (e.g., yield strength), choose buckling curve, calculate slenderness and finally arrive at an estimate for a buckling multiplier that includes the (approximated) effect of initial imperfections.

PS. Eurocode 2, which covers reinforced concrete design, is not very specific about buckling due to the fact that reinforced concrete compression members very rarely fail due to buckling. Detailed buckling analysis is most often done for steel structures, which are covered in the Eurocode 3 standard.

 

[JoshPlumSE]

There are two types of buckling to think about:

a) Elastic Buckling. This is based on unbraced length, Young's modulus and moment of inertia. Elastic buckling generally occurs for longer, slender members.

b) Inelastic Buckling. This, like elastic buckling, is based on length, young's modulus, moment of inertia. But, it is also based on yield strength. Elastic buckling happens when the member is not slender enough to buckle elastically, but yielding of the extreme fibers cause this inelastic buckling to occur at a lower load.