What does the "10" in a W10 × 30 steel beam specification represent?

In the specification W10 × 30 for a steel beam, the "10" represents the nominal depth of the beam in inches. The number indicates the overall depth measured from the top of the flange to the bottom of the flange, which is a crucial dimension in structural design as it affects both the strength and stability of the beam.

Understanding this designation is important for engineers and constructors, as it helps in sizing beams for specific load requirements and structural configurations. The second part of the designation, "30," indicates the weight of the beam, specifying that it weighs 30 pounds per foot. This system of naming can be a bit confusing, but recognizing that the first number corresponds to depth assists in correctly identifying a beam's size and application in construction projects.