Eriksson Wall allows two methods to analysis composite wall panels. These methods are the percent composite method and using a beam spring model.
Percent Composite
For more information on the theory of a percent composite analysis, see Percent Composite.Inputs exist to set the percent composite value for stripping, transportation, erection, and in-place. The construction stage uses the same percent composite values are in-place. For each of these stages, the user can give a percent composite for deflections, stress calculations, and all strength checks.
For service checks, deflections and stresses, the percent composite is used by interpolating the section properties between fully composite and non-composite. The non-composite section used for all interpolation contains only the structural wythe and the non-structural wythe is not considered.
For strength checks the percent composite is used by interpolating between capacities by the defined percent composite. For example, for an 80% composite panel, the flexure capacity would be 80% of the way between the non-composite and fully composite flexure capacity. Because of this accurate parameters used in computing capacities are not known (such as neutral axis depth). The PM Diagram is also interpolated between the non-composite and fully composite case.
The following options are also selected by the user:
Header | Description |
|---|---|
Deflections | Percent composite value used for the structural analysis. |
Stresses | Percent composite value used for all stress computations. |
Strength | Percent compute used for ultimate strength. |
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Header | Description |
|---|---|
Solid zone behavior | Partial Composite: Will treat all sections where the wythes are connected by concrete as partially composite. Fully Composite: Will treat all sections where the wythes are connected by concrete as fully compositeThis controls how solid zones are to be handled in the analysis. If set to partially composite, all the concrete in the solid zone is considered top-in-form as it is considered part of the secondary pour. If set to fully composite the section will not use any interpolation for section properties or strength checks. |
Structural wythe | Sets which wythe to use as the non-composite wythe when interpolating. The options are Top-in-Form, Bottom-in-Form, and Stiffer Wythe. If Stiffer Wythe is selected, whichever wythe has the larger EI value will be used. |
Loading datum | Sets which section should be used when determining the eccentricity of a given point load. Since the loads are input relative to a given face, the input eccentricity is only part of the total eccentricity. The section options are: Deflection Section, Stress Section, Ultimate Section, Composite Section, Non-Composite Section. |
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Header | Description |
|---|---|
Rows | The number of rows in the input region. |
Columns | The number of columns in the input region. |
Transverse Method | Sets which two of the three available options you want to set: Left Distance, Width, or Right Distance. |
Left Distance | The distance from the left edge of the panel to the first column. |
Width | The distance from the first column to the last column. |
Right Distance | The distance from the right edge of the panel to the last column. |
Longitudinal Method | Sets which two of the three available options you want to set: Bottom Distance, Length, or Top Distance. |
Bottom Distance | The distance from the bottom of the panel to the first row. |
Length | The distance from the first row to the last row of connectors. |
Top Distance | The distance from the top edge of the panel to the last row. |
Stiffness Multipliers | A multiplier applied directly to the stiffness values of the connectors. These multipliers do not change limit slips, just scales the stiffness. Can be used to model solid zones in the concrete. |
Solid Zones
The beam spring model will always splint forces between the two wythes, even when a solid zone (such as an end block) is connecting them. In the figure below, the two wythes are connected by rigid links connecting the centroid of each wythe. Options exist to connect all of the solid zones, none of the solid zones, or only the end blocks. Typically by just having end blocks, the slip in the panel goes near zero rendering other connectors meaningless for shear transfer.