The RM Bridge Analyzer: Properties: Cross Sections: Parts menu is used for viewing and managing the cross-section Parts parameters information stored in the database.
Usually, the cross-section parts can be required for 2 reasons:
- Dividing: The total cross-section can be subdivided into several individual cross-sections. For example, several longitudinal girders of a girder grid model.
- Composite: For the definition of composite cross-sections. In addition to the connected individual parts, the user must define a separate numbered "part" representing the composite cross-section.
The menu is distributed in the Windows' four areas, that have their respective sub-functions:
- Top left table: Cross-section basic parameters
- Top right graphic: Cross-section graphical view
- Bottom left table: Parts of the selected cross-section
- Bottom right table: Cross-section values for the selected cross-section part
- Top Left: The upper table shows all defined cross-sections' basic parameters with the following:
- Group: The group name of the cross-section
- Name: Name of the individual cross-section (variant of grouped cross-sections)
- Catalog Name: The name of the respective catalog cross-section if the cross-section is from the predefined cross-section catalog.
- Parts: Number of individual parts of the cross-section
- Top right: The graphic presentation of the cross-section shows all its parts, with the part currently selected in the lower left table drawn in signal color (red).
- GraphSet: Function for modification of the presentation with the selection of presented properties of the whole cross-section
- PartSet: Function for modification of the presentation with the selection of presented properties of the currently selected cross-section part
- ShStr: Function for presenting shear stress vectors due to unit internal forces (optionally for Qy, Qz or Mx = 1.0) for the currently selected cross-section part
- ShStr: Display of the maximum shear stress value in the presented Gauss points
- MarkPart: Option for switching on or off the marking of the currently selected part
- StrFact: Factor for the presentation of the shear stress vectors
- Zoom: Option for maximizing the presentation of the current cross-section part
- Bottom left: Table of cross-section parts
- Part: Number of the cross-section part
- Type: Type of the cross-section part
- Static: The part is effective for the stiffness calculation
- Weight: The part is only considered for calculating the self-weight of the members.
- Slave: The cross-section part is not a physical part but a fictitious part describing the position of a so-called slave node with separate degrees of freedom. These DOFs are used in a Finite Element analysis using shell or volume elements to allow for the deformation of the cross-section.
- Cls: Class of the cross-section part. This class term refers to the cross-section categories of Table 6.2 of Eurocode EN 1993-1-1. It is used in steel design checks to select the relevant buckling curve and calculate the cross-section class with respect to local buckling hazard (cross-section classes 1 to 4 in Eurocode or classes "Compact," "Non-compact," and "Slender" in AASHTO code).
- Solid: A general, more or less compact section that does not belong to a special class as defined below (also C profiles (channels) and T profiles).
- I-R (I-rolled): Rolled I or H profile.
- I-W (I-welded): Welded I or H profile.
- L (I-rolled): Rolled angle profile (equal or unequal legs)
- BRh (Box rolled hot): Hot rolled hollow profile (rectangular box or pipe)
- BRc (Box rolled cold): Cold rolled hollow profile (rectangular box or pipe)
- BW (Box welded general): General welded hollow box profile
- BWs (Box welded special): Welded hollow profile with thick walls and welds
- R-Mx, R-Qy, R-Qz: Reduction factors for calculating the torsional stiffness and the shear stiffness in y and z direction.
- y, z: Position of the origin of the coordinate system of the cross-section part in the coordinate system of the total cross-section.
- Parts: For composite parts: Numbers of individual parts forming the composite part.
- Bottom right: Table of the cross-section values for the selected cross-section part, contains different parameter sets dependent on which of the 4 radio buttons above the table has been selected.
- Bend.: Display of standard cross-section values related to the local coordinate system of the cross-section translated into the center of gravity. The torsional moment of inertia is calculated around the shear center but used as if releated to the center of gravity.
- Ax: Cross-section area
- Ay, Az: Shear area for shear in y and z directions
- Ix: Torsion moment of inertia (calculated around the shear center)
- Iy, Iz: Bending moments of inertia around y and z directions respectively
- Iyz: Biaxial moment of inertia (not used, just for information)
- Wy,pl; Wz.pl: Plastic section modulus around y and z directions respectively
- Shear: Display of the parameters governing the shear behavior
- sx: Factor X (Ax-schub / Ax) - reduction of cross-section area due to shear lag
- eslz: Eccentricity ez (center of gravity of reduced cross-section)
- sy: Faktor Y for reduction of cross-section area due to shear lag
- Iy*sy: Moment of inertia Iy considering reduction of cross-section area due to shear lag
- esly: Eccentricity ey (center of gravity of reduced cross-section)
- sz: Factor Z for reduction of cross-section area due to shear lag
- lz*sz: Moment of inertia Iz considering reduction of cross-section area due to shear lag
- lw: Warping resistance (not used)
- Ecc.: Display of the geometric position of center of gravity and shear center
- ey, ez: Distance of the center of gravity from the coordinate origin
- Beta: Angle of principal axes of inertia
- ey-s, ez-s: Distance of the shear center from the coordinate origin
- ey-pl, ez-pl: Distance of the center of plastic bending from the coordinate origin
- Beta-pl: Angle of principal axes of plastic bending
- Geom.: Display of additional interesting geometric parameters
- y1, a2: Distance of the center of gravity from bottom and top respectively
- y1, a2: Distance of the center of gravity from the left and right edge respectively
- U: Perimeter of the cross-section (outside)
- UIN: Perimeter of any voids in the cross-section (inside)
- Variant: Cross-section variant if the same cross-section is used in different way
- Bend.: Display of standard cross-section values related to the local coordinate system of the cross-section translated into the center of gravity. The torsional moment of inertia is calculated around the shear center but used as if releated to the center of gravity.