Section Modulus Formula

Where i moment of inertia y distance from centroid to top or bottom edge of the rectangle.

Section modulus formula. I a 4 12. Z p d 3 6. 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.

Z p d 2 3 d 1 3 6. For asymmetrical sections two values are found. Z x b h 2 h 4 b h 2 h 4 bh 2 4.

Z a 3 6 2 i a 12 0 28867a. The ratio i cis called the section modulus and is usually denoted by swith units of mm3 in3. To calculate the section modulus the following formula applies.

Displaystyle z p cfrac d 3 6 circular hollow section. A a 2. I a 4 12.

Calculating the section modulus. A area units 2 e extreme point units i moment of inertia units 4 z section modulus units 3 i e i radius of gyration units i a square. E a 2.

Displaystyle z p cfrac d 2 3 d 1 3 6 the plastic section modulus is used to calculate the plastic moment m p or full capacity of a cross section. The elastic section modulus is defined as s i y where i is the second moment of area or moment of inertia and y is the distance from the neutral axis to any given fiber. For symmetrical sections the value of z is the same above or below the centroid.