IES ShapeBuilder User's Guide
Advanced Results
| Nodes |
The number of nodes used in the analysis mesh. |
| Elements | The number of elements used in the analysis mesh. |
| Largest Element | Area of the largest plate element in the mesh, determines mesh refinement |
Normal stress is calculated for composite sections with multiple materials.
| Combined Axial & Flexural Stress, σz |
Normal stress (combined axial and bending). Normal stress is positive for tension, negative for compression. where:
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The accuracy of these calculated values depends upon the mesh density used in the finite element analysis, see Analysis Settings for more details on improving the accuracy of your results. Advanced analysis is not performed on a shape composed of multiple disconnected parts or for composite shapes (i.e when multiple materials are defined). The theory is based on a single material and the warping normal functions. Beware of using "superposition" of your parts independently to estimate a J value, as your results may not be correct.
| Polar Radius of Gyration about the Shear Center, ro |
The polar radius of gyration about the shear center is defined in AISC 360 Specification Chapter E Commentary as: Note: This property is only shown if the shear center does not coincide with the centroid. See also rp in the Simple Results. |
| AISC Flexural Constant, H |
Derived from the polar radius of gyration about the shear center is the AISC flexural constant: Refer to the AISC manual for more details. H=1 if the shear center and centroid coincide. |
| Shear Center, Xsc, Ysc | Also known as the Flexural Center. The Shear Center is the point on the cross section where an applied shear force will cause no twisting of the cross section as it bends. In general, this is not the centroid. If the section is symmetric, the shear center will lie on the axis of symmetry; for doubly symmetric sections, the shear center will coincide with the centroid. This point is located with respect to the global origin. |
| Warping Constant, Cw |
Warping constant is calculated as: where ω is the warping function |
| Torsion Constant, J |
Torsional stiffness factor is a more accurate measure of the torsional rigidity than polar moment of inertia. The approximate equations for thin-walled open sections and thin-walled closed sections are given below. ShapeBuilder uses a sophisticated numerical process to calculate the value, which may be quite different than the approximation formula results. |
| Monosymmetry Factor, B1 |
Used for calculating lateral torsional buckling of singly-symmetric cross sections. [See reference Trahair and Nethercot]. |
More information on the above parameters can be found in the References section.
These require the full FEA analysis.
| St. Venant, τxy, τyz | Shear stress due to torque only. These stresses are also called uniform torsional shear stresses. |
| Warping Function | The normalized warping function (length^2). This is not a stress and it is not load-dependent. |
| Flexural, τxy,τyz | Shear stresses induced by the applied shear loads. |
| Combined, τxy, τyz | The superposition of Flexural and St.Venant shear stresses. |
| Resultant, τ | Resultant shear stress found by taking the square root of the sum of the squares of the Flexural and St. Venant shear stresses. The resultant represents the vector resultant value that is a positive number. |
| First Moment of Area, Qx, Qy |
The first moment of area of the individual part or the region defined by the shear flow location about the centroid of the entire built-up shape. The first moment of area is used to determine the shear flow (VQ/I). |
| Shear Flow, f(Vx), f(Vy) |
The shear flow due to the shear force in the X-direction (Vx) and the shear force in the Y-direction (Vy). These values are calculated for each part and for the regions defined by the shear flow locations. |
