Section Modulus calculation and optimization

Section modulus

Section Modulus is a geometric property used to calculate the bending stresses in a structural member. It is defined as the ratio of the moment of inertia of a section about its centroidal axis and the distance of the extreme layer from the neutral axis.

Section modulus, S = I/y

Where,

S - Section modulus

I - Area moment of inertia

y - Distance between neutral axis and extreme end of the fibre

Therefore, I (min) = 1.516× 10^4 mm^4

y = 885.3761/2

= 442.688 mm

Section modulus, S1 = 1.516× 10^4mm^4 / 442.688 mm

S1 = 32.2453 mm^3

Cut section of original section

Moment of Inertia about neutral axis


y distance of section modulus

Section Modulus of the modified section after offsetting the edges of inner hood panel by 1.5mm away from outer hood panel

I (min) = 1.5646× 10^4 mm^4

y = 885.3761/2

= 442.688 mm

So, Section modulus,

S2 = 1.5646× 10^4 mm^4 / 442.688 mm

S2 = 35.343 mm^3

Percentage increase in section modulus

(S2-S1/ S1) * 100 = 9.606%