Analysis Methods

Analysis Methods for Splices & Moment Connections

The distribution of forces between the flanges and web in BSPL, WSPL, BMEP, HBEP, and WBC connections is determined by the analysis method set with the File > Configure > General command. There are three different analysis methods - these are elastic, plastic, and simplified (only available with AISC LRFD and BS 5950).

The elastic method is recommended in Ref. 4 and the AASHTO 1999 Interim. Plastic analysis gives a more rational force distribution when the factored loads are sufficient to cause yield. Other analysis methods may then produce flange forces that exceed the capacity of the flange. The elastic method is the default for checking to AS 4100. The simplified method is a traditional approach in which the flange plates are assumed to resist all the moment and axial force while the web plates resist the shear (and the resulting eccentricity moment). Choosing the simplified method gives designs with stronger flange plates and weaker web plates. It is the default method when Limcon is configured for AISC LRFD or BS 5950.

All three analysis methods give safe, lower bound, designs but the simplified method leads to more yielding and redistribution of forces as the connection conforms to the applied loading.