ABSTRACT
The geometrical properties of sections are of great importance in a number of different branches of engineering, including stress analysis. For example, if a beam is subjected to bending action, its bending stiffness will depend not only on the material properties of the beam, but also on the geometrical properties of its cross section. Typical beam cross-sections for symmetrical sections include circular, rectangular, triangular, I and T sections.
The strength of a structure is not only dependent on the material properties of the structure but also on its geometrical properties. For example, the strength of a wire in tension is also dependent on the size of its cross-section. Likewise, the strength of a beam in bending is also dependent on its ability to withstand bending and torsion, besides its size. Since the invention of steel, the strength of a beam can be increased by the shape of its cross-section, in addition to the size of its cross-section. This has been achieved by the introduction of flanges, etc, in its cross-section, which could not be achieved with wooden structures in the past. Also, the ability of the water plane of a ship to withstand movement due to rolling and trimming, together with immersion, is also dependent on the size and shape of its water plane.
