Column properties
Column properties
General | |
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Name | The automatically generated name. |
User Name | Can be used to override the automatically generated name if required. |
Group | The name of the group to which the member belongs. See: Concrete member design and detailing groups , Steel member design groups |
Top Level | Specifies the top level for the column. |
Base Level | Specifies the bottom level for the column. |
Plane | Indicates the grid along which the wall is placed. |
Characteristic | Column |
Material type |
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Construction, Fabrication |
The available construction and fabrication options depend on the characteristic and material type selected, see Member characteristic, construction and fabrication properties |
Autodesign | |
Design section order (steel only) |
The design order file from which a section size will be selected. Note: Only displayed for Autodesign
For details of managing order files, see: Manage design section orders |
Select bars starting from (concrete only) |
This option controls the starting point for auto-design procedures and is therefore only displayed if Automatic design is ‘on’. It applies to both longitudinal bars and links. • Minima (default) - removes the current arrangement and begins with the minimum allowed bar size. • Current - the auto design commences from the current bar arrangement. |
Gravity only | Controls whether the member is defined for gravity combinations only, or gravity plus lateral:
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Rotation |
Rotation of the column about its local x axis. Note: For a vertical column:
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Assume extra floors supported | Enter the number of extra floors supported. |
Simple column (steel only) |
See: Simple columns |
All stacks | |
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Section | The section size |
Concrete type, Grade/Class (Concrete columns only) |
While you can apply both normal and lightweight concrete, wall design using lightweight concrete is currently beyond scope. |
Alignment (concrete only) | |
Major snap level, Minor snap level, |
Define the major and minor alignment of the member relative to the insertion point. |
Major offset, Minor offset |
Used to offset the member from the snap point in the major and minor axis. |
Face A cont. rest., Face C cont. rest. (steel only) |
Indicates continuous restraint to Face A and/or Face C. |
Releases | |
Fixity Top, Fixity Bottom |
See: Column releases |
Axial load release top | An axial (Fx) release is only allowed at the top of the column. |
Torsional load release top, Torsional load release bottom |
Check one end only to define a torsional release. |
Size constraints (steel only) | |
Max depth, Min depth, Max width, Min width |
Size Constraints are only applicable when Autodesign is checked. They allow you to ensure that the sections that Tekla Structural Designer proposes match any particular size constraints you may have. |
Instability factor (steel only) | |
Prevent out of plane instability | Define if out of plane stability is prevented. See: Instability factor |
Design control (concrete only) | |
Assume cracked | Assuming concrete sections are cracked has a direct affect on the analysis; smaller Modification Factors are applied to cracked sections causing an increase in deflection. Indirectly the design can also be affected because the sway/drift sensitivity calculations are also influenced by this assumption. |
Apply rigid zones | Unless cleared, rigid zones are automatically created at the connection between the column and any connecting beams. |
Design parameters (Eurocode only) | |
Permanent load ratio option Relative humidity (RH) Age of loading |
You are required to supply a value for the permanent load ratio parameter. A default of 0.65 has been assumed, but you are advised to consider if this is appropriate and adjust as necessary. Age of loading is the age at which loading is applied. |
Confinement reinforcement (concrete only) | |
Provide support regions | • Checked - confinement reinforcement is designed separately in three regions. • Cleared - the same confinement reinforcement is designed for the whole stack. |
Slenderness (concrete only) | |
Direction 1, Direction 2 |
• Braced • Bracing |
Direction 1 effective length factor, Direction 2 effective length factor |
• Calculated • User input value |
Stiffness (concrete only) | |
Use slab for calculation upper, lower | For the unrestrained length calculation: • if a slab exists at a panel end, it can be ignored by unchecking the relevant box. • If no slab exists at that end, the setting is redundant - in which case the program considers the setting at the remote end of the next panel instead. See: Stiffness |
Sway and drift checks | |
Merge with stack below | Columns are divided into stacks and walls are divided into panels at floor levels where members or slabs connect to the column/wall. For the purposes of Sway/Drift, Wind Drift and Seismic Drift checks only you can override the default stack/panel divisions by merging a stack/panel with a lower stack/panel. The length of the combined stack/panel is then used in the checks. |
Sway/Seismic drift checks | By default all stacks of all columns are taken into account in the calculation to determine the sway sensitivity of the building. The results of this calculation being accessed from the Review toolbar. This parameter provides a facility to exclude particular column stacks from these calculations to avoid spurious results associated with very small stack lengths. You can either clear the check box located under ‘All Stacks’ to exclude the entire column, or you can exclude a particular stack by clearing the check box located under that stack only. |
Wind drift check, Wind drift ratio |
Wind drift is automatically checked against the specified limiting ratio, (which can be set differently for different columns). The results of this calculation are accessed from the Review toolbar. If you don’t want this check to be performed you can either clear the check box located under ‘All Stacks’ to exclude the entire column, or you can exclude a particular stack by clearing the check box located under that stack only. |
Nominal cover | The nominal concrete cover is the distance between the surface of the reinforcement closest to the nearest concrete surface (including links and surface reinforcement where relevant) and the nearest concrete surface. |
Seismic | |
In a seismic force resisting system | If this is the case, select the check box, and then specify the SFRS direction and type. Note: Design of members in seismic force resisting systems is only supported for the ACI/AISC Head Code in the current release.
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Shear demand/shear capacity ratio in Dir 1 Shear demand/shear capacity ratio in Dir 2 (ASCE7 code only) |
When working to the ASCE7, the engineer can directly define the shear demand / capacity ratio (beta) in each direction. The default value of 1.0 could be over-conservative. The setting is applicable to all years of the ASCE7 code and has the following default and limits: Default = 1; Min = 0.001; Max = 10. |
Utilization ratio | |
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Apply (to autodesign) | On
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Apply (to check) | On
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Ratio limit | The utilization ratio against which the autodesign or check is performed (when applied above). |
UDA | |
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Name Finish Class Phase Note File |
A customizable list of the attributes that can be applied to individual members and panels. |
Reinforcement | |
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Rib type - vertical, Class - vertical | Specifies the vertical reinforcement properties |
Rib type - link/confinement, Class - link/confinement | Specifies the link/confinement properties. |
Stack 1, 2, 3 etc. | |
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In a multi-stack column properties can be entered for a specific stack, over-riding those defined at the All stacks level. |
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Splice, Splice offset |
Used to indicate a splice at the bottom of a stack, and the offset above the floor level. |
Level 1, 2, 3 etc. | |
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Load reductions | |
KLL (Head Code ACI/AISC) |
Specify the KLL factor in accordance with Table 4-2 in ASCE7-05/ASCE7-10. |
Count the floor as being supported (Head Code Eurocode, BS or IS) |
If checked, the floor will be treated as supported when calculating the live/imposed load reductions. |
Eccentricity (steel only) | |
Apply face A eccentricity, etc. |