Section Modulus Equation

The elastic section modulus is defined as s i y where i is the second moment of area or area moment of inertia not to be confused with moment of inertia and y is the distance from the neutral axis to any given fibre.

Section modulus equation. This engineering data is often used in the design of structural beams or structural flexural members. Calculating the section modulus to calculate the section modulus the following formula applies. Z a 3 6 2.

I a 4 12. Z a 3 6. Section modulus is a geometric property for a given cross section used in the design of beams or flexural members.

Z x b h 2 h 4 b h 2 h 4 bh 2 4. S i c c. I a 4 12.

Area moment of inertia section properties of rectangular feature calculator and equations. Section modulus the maximum bending stress in a beam is calculated as σ b mc i c where c is the distance from the neutral axis to the extreme fiber i c is the centroidal moment of inertia and m is the bending moment. The section modulus combines the c and i c terms in the bending stress equation.

Other geometric properties used in design include area for tension radius of gyration for compression and moment of inertia for stiffness. E a 2. The plastic section modulus for a rectangular cross section can be determined by multiplying each section half e g the shaded area shown in figure 1 50 by the distance from its centroid to the centroid for the whole section.

Section modulus equations and calculators common shapes. It is often reported using y c where c is the distance from the neutral axis to the most extreme fibre as seen in the table below. For symmetrical sections this will mean the zx max and zx min are equal.