Section Modulus calculation and optimization

What is Section Modulus?

Section modulus is a geometric property for a given cross-section used in the design of beams or flexural members.

Also section modulus is a direct measure of strength od flexural member. Higher the section modulus higher will be resistance for bending.

Section modulus is ratio of Area moment of inertia to the distance from the neutral axis to the point where the Bending normal stress is determined.

Section Modulus(S)=`frac{I}{Y}`.

Where I=Moment of Inertia of member.

Y=Yield strength of member.

Section modulus calculations of hood:

From The above design section, minimum moment of inertia is 73.2396 `mm^4`.

considering yield strength for AISI 302cold rolled stainless steel is 520 Mpa.

For section modulus,

S=`frac(I)(Y)`

=`frac(73.2396)(520)`

=0.1408 `mm^3`.

In order to increase resistant to bending of Hood, we have to improve the section modulus of hood.

From the above equation it can be observe that th section modulus of body is directly proportional to the area moment of inertia.

so for improving section modulas we have increase are moment of inertia.

I have made some changes according to that in hood section shown in below:

From the above design section , min. moment of inertia is 82.16 `mm^4`.

considering yield strength for AISI 302cold rolled stainless steel is 520 Mpa.

For section modulus,

S=`frac(I)(Y)`

=`frac(82.16)(520)`

=0.158 `mm^3``

From the above calculation it is observed that we improve the section modulus value by 0.017 `mm^3`.

So that we made improvement in bending resistant of hood.