Neutral Axis
Definition
The axis within a beam cross-section where bending stress is zero. Fibers above the neutral axis are in tension or compression (depending on bending direction), while those below are in the opposite state.
Practical Note
For homogeneous beams, the neutral axis passes through the centroid. For composite beams (e.g., reinforced concrete), the neutral axis shifts toward the stiffer material.
Related Calculators
Calculate moment of inertia (second moment of area), section modulus, and radius of gyration for common cross-sectional shapes including rectangles, circles, I-beams, and channels.
Calculate maximum deflection, bending moment, and stress for simply supported and cantilever beams. Includes 3D visualization.
Calculate stress, strain, and elastic modulus from basic inputs. Includes true stress/strain conversion, Poisson's ratio effects, and interactive stress-strain curve visualization.