Steel structure cow leg is a cantilever system hanging beam and cantilever between the inevitable shelving structure, that is, the cantilever end and the hanging beam end of the local structure is called the cow leg, also known as the beam bracket. In ancient architecture, the scientific name of the bull's leg is called propping arch.

Cow legs can be used equal section, can also be used variable section; variable section cow legs, the end section height should not be less than half of the height of the root. In the calculation of the connection weld between the bull's leg and the column, the connection weld between the bull's leg flange plate and the column should be a weld-through butt weld, and the connection weld between the web and the column can be an angle butt combination weld or an angle weld, and the size of the weld leg of the angle weld is determined by the shear force V.