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.
- 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.
- 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
- BS 5950-1:2000 - Structural use of steelwork in building - Part 1: Code of practice for design - Rolled and welded sections.
- Ver 1.0 - Original version