1. About & Disclaimer

    This design software calculates the elastic critical moment for lateral-torsional buckling (Mcr).This tool covers the scope of NCCI SN003b-EN-EU and is limited to doubly open symmetric members (Advance ® UKB and Advance ® UKC) subject to end moments and transverse loads. Transverse loads may be applied as a uniformly distributed load (UDL) or a central point load. The point of load application may be specified at a distance zg from the shear centre to account for destabilising loading (positive dimensions from the shear centre) or stabilising loading (negative dimensions from the shear centre). If the loading includes end moments, the ratio of end moments (smaller value/larger value) is required. Absolute values of loading are not required for transverse loads alone, as only the shape of the bending moment diagram is relevant, not the absolute values. Members with fixed ends may produce a negative value of (Mcr), depending on the direction of the loading. The positive value should be used in subsequent calculations of the non-dimensional slenderness.

    Although care has been taken to ensure that the calculated values are correct, users should verify the output. The Steel Construction Institute and other parties associated with this software and website assume no responsibilities for errors or misuse of this software, or damage arising from use of this software.

  2. Provide Input
    Select section type, section, span, loading type, support condition, loading condition, distance between load application point and shear centre, uniformly distributed load, point load, maximum end moment, ratio of end moments.
  3. Calculate and review Output
    Launch calculation and review the results