Is Section Modulus the same as a cross sections bending strength modulus ?

1. Mech King

73
Is "Section Modulus" the same as a cross sections "bending strength modulus"?

Good afternoon everyone,

I am following an ECE directive that sets out the requirements for the properties of a "Rear underun protection device" for the rear of a lorry.

It states that the underun bar must consist of a "steel beam whos cross-section has a bending strength modulus of at least 20cm^3"

Are they refering to the "Section modulus"? or is what they are stating a completly differnt entity.

Trying to find the appropriate person to speak to for this directive is proving abit of a nightmare, oh the joys of bureaucracy eh!

Mech King

2. Nick Bruno

100
Re: Is "Section Modulus" the same as a cross sections "bending strength modulus"?

From the looks of the information given, I would say it is indeed the section modulus because the unit is volume.

I believe bending strength modulus is the same as flexural modulus defined as:

EI or N/m^2 * m ^4 = N*m^2

Please correct me if i am wrong, but this is my take on this.

3. nvn

2,124
Nick Bruno: No, flexural modulus of elasticity has units of Pa (pascals), as does tensile modulus of elasticity. And E*I, which has units of N*m^2, is called flexural rigidity, not the names you listed.

Mech King: I agree that "bending strength modulus" in your above post is elastic section modulus.

4. Mech King

73
Re: Is "Section Modulus" the same as a cross sections "bending strength modulus"?