Cross-sectional characteristics
The cross-sectional characteristics can be calculated in two different ways:
- Real cross-sectional characteristics are calculated according to the geometry of the cross-section and are not affected by the material.
- Ideal cross-sectional characteristics are important for combined cross-sections with more different materials (e.g. concrete and steel). Ideal characteristics are the characteristics recalculated for the material, that can be specified in the upper part of the frame with results. Recalculation is based on the proportion of moduli of elasticity. This ensures, that all parts are deformed in the same way when exposed to tension, compression or bending. The areas and moments of inertia are multiplied by the factor n:
Where is: | E0 |
|
Ei |
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Available cross-sectional characteristics
Following characteristics are calculated:
- The centre of gravity in coordinate system - xT and yT
- The cross-sectional area - A
- The cross-sectional perimeter - P
- The centre of gravity with respect of the left bottom corner of minimum cross-sectional envelope - ycg, zcg
- Moments of inertia - Iy, Iz, Dyz
- Rotation of main axes - φ
- Radii of inertia - iy, iz
- Polar moment and radius of inertia - Ip, ip
- Rigidity moment in simple torsion - Ik
- Cross-sectional moduli in edges - Wy1, Wy2, Wz1 , Wz2