Structural steel is acategory of steel used for making construction materials in a variety of shapes. Many structural steel shapes take the form of an elongated beam havinga profile of a specific cross section. Structural steel shapes, sizes, chemicalcomposition, mechanical properties such as strengths, storage practices, etc.,are regulated by standards in most industrialized countries.

  Most structural steelshapes, such as I-beams, have high second moments of area, which means they arevery stiff in respect to their cross-sectional area and thus can support a highload without excessive sagging.