The K-factors for beams and braces can be specified by the user using the Criteria – Effective Length command, or on a member-by-member basis using the Assign menu. The Ke-factors for columns can be either specified by the user or calculated by the program. For braced frames the calculated value is always 1.0. For unbraced frames the calculated value is based on an approximation to the graphs provided in AS 4100 -98 section 4.6.3.3. The approximation is currently based on the AISC nomograph equations. If the user is not satisfied with the values calculated by these equations they should assign the effective length value directly to the members.

For determining γ at column bases the following rules are followed. γ is limited to 10.0 for columns when there are no beams framing in, or when only pinned end beams are framing in; this limits ke to a value of 3.0, rather than the theoretical value of infinity. γ is limited to 0.6 at the bottom of the column if it is fixed to the footing. Columns that are pinned top and bottom are given ke-factors of 1.0. Knee brace columns are assigned a ke factor of 1.0 in the direction of the knee brace. If a spring exists at the base of a column the spring rotational stiffness is considered as the γ that end of the column.