Spacing of channel helps to increase the MOI in that direction.

Compression members are more critical since they have to resist buckling. The imperfections of cross section dimensions, eccentricity of the load, lateral loads, residual stresses, punched holes, erection stresses are some of the other important factors which contribute to unwanted stresses making compression members more critical.

To decrease size of gusset plate

Used when connection length is limited.

The shear lag reduces the effectiveness of the component of the section which is not connected to the gusset plate. This results in a decrease in the strength of a tension member. Therefore, area of steel in outstanding leg should be as small as possible. This consequently, results in unequal angle section with long leg connected since this will be more efficient.

Yielding of Gross Section

Net Section Rupture

Block Shear Failure

Minimum pitch = 2.5d

Maximum pitch,

For compression member – 12t or 200mm whichever is less

For Tension Member – 16t or 200mm whichever is less