In concrete structural systems, what is a common span range for one-way beams and girders?

The common span range for one-way beams and girders is typically found in the range of 15 to 30 feet. This range is suitable for many design scenarios, as one-way beams are often used in buildings where loads are primarily acting in one direction.

Spans in this range allow for efficient use of materials and control of deflection. In particular, one-way beams effectively support floor systems—such as concrete slabs—transferring loads to the supporting elements like columns or walls.

The other span options either extend too far for practical applications of one-way structural elements or fall short of what is typically efficient or economical in construction practice for familiar scenarios. Understanding this span range helps architects and engineers decide on appropriate structural systems for different design conditions.