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Calculations   >   Steel   >   Crane Gantry Girder Design

Crane Gantry Girder Design

The scope of this calculation module is to analyse and design a steel gantry girder section used to support overhead crane. The section profile can be either I section (rolled or welded) or built-up section (rolled I section with capped channel or plate). The section is checked for moment and shear capacity ratios along with deflection due to moving loads from crane.

Standards: British.

Features

  • The girder’s cross section can be defined using the following shapes:
  • Rolled I section
  • Rolled I section with channel
  • Rolled I section with plate
  • Welded I section
  • Wheel loads on the section is considered using the following options:
  • User defined wheel load
  • The user is allowed to input the wheel loads directly.
  • Crane details
  • The module calculates the wheel loads based on the defined crane arrangement.
  • Additionally, an option is provided to select the span position as interior or end span.
  • Effective length factor of the girder is calculated based on the restraint condition of the section which can also be defined by the user directly.

Design Considerations

  • The elastic and plastic section properties of the section are referred from steel table for standard sections and are calculated for built-up and welded I sections. For built-up section, combined section properties are considered for the calculation.
  • For direct static wheel load option, dynamic wheel and surge loads are calculated based on the dynamic factors whereas, crab load is calculated based on the crane class.
  • The program computes moment and shear capacity only for sections classified as ‘plastic’, ‘compact’ or ‘semi compact’.
  • Forces in the lateral direction are considered to be resisted by the top flange of the section.
  • Weld capacity is checked for built-up section (rolled I section with capped channel or plate) alone.
  • Vertical and horizontal deflections are calculated and compared with allowable limit.

National Standards Available

British Standard

References

  • BS 5950-1:2000 - Structural use of steelwork in building - Part 1: Code of practice for design - Rolled and welded sections.

Revision

  • Ver 1.0 - Original version