The American Society for Testing and Materials, or ASTM, is an organization that standardizes specifications for materials, systems and equipment worldwide. One such standard involves steel. ASTM A36 is a standard for a certain type of carbon structural steel.
What is Shear Stress?
Shear stress refers to a pressure endured by a material parallel to its face. Shear strength is the material's ability to endure this applied stress. If enough stress is applied to a body it may not return to its original shape. Picture a rubber band. If the band is stretched a little bit it will return to its original shape. However, should the rubber band be stretched beyond a certain point it will snap and therefore, not return to its original shape. This "certain point" is called the yield strength. Stress is a measurement of pressure and therefore is measured using the same units. The units are usually pounds per square inch (PSI) or newtons per square millimeter.
The standard yield strength of A36 steel is 36,000 PSI or 250 newtons per millimeter squared.
A36 steel comes in a variety of forms. These forms include plate, pipe, bar and sheet. Although these forms have different thicknesses, sizes and shapes, the yield strength will still remain the same as per ASTM standards.