Neutral Axis and Flexural Formula Definition

Hi Keith, let's explore the theory of simple bending by defining the neutral axis and the flexural formula.

First, let's look at the Neutral Axis. When a beam is subjected to bending, some fibers are in tension and some are in compression.

The Neutral Axis is the layer or longitudinal axis of the beam that undergoes no change in length during bending. This means there is zero strain and zero stress on this axis.

Now, let's state the flexural formula, also known as the bending equation.

This formula relates the internal bending moment to the stress and physical properties of the beam. Let's break down each term.

M represents the internal bending moment acting at the cross-section, usually measured in Newton millimeters.