What is the standard hook length for a #5 bar?

The standard hook length for a #5 bar, often used as a reinforcing steel bar in concrete structures, is indeed 10 inches. This measurement is integral to ensuring proper anchorage and development of the reinforcing bar within the concrete, which is crucial for maintaining structural integrity.

When a reinforcing bar is bent to create a hook, there are guidelines set in various design codes, like the American Concrete Institute (ACI), that specify the length of the hook depending on the diameter of the bar. For a #5 bar, which has a diameter of 5/8 inches, the standard hook length is determined to be 10 inches. This ensures that the bar is embedded sufficiently to transfer the stresses from the concrete to the steel effectively.

Understanding the proper hook length is essential for civil engineers and practitioners to prevent issues such as pullout of the bar from the concrete, which can compromise the overall performance of the structure.