Function
- Torsional Irregularity is checked for static and dynamic loads, and the status of irregularity is tabulated in a spread sheet format.
- When "Story Shear Force Ratio>Consider Story Module"is checked in the "Model/Building/Control Data", accurate shear forces can be obtained for the story having the overlapping Module.
- When Modules are defined in Structure > Building > Story > Define Module button, the Module data is displayed in the first column of the table.
- When the ratios exceed the allowable limit, they appear in red and 'Irregular' is printed in the Remark.
- Table Tool in Gen NX offers a variety of powerful built-in functions. Refer to Usage of Table Tool for detail directions.
Call
From the Main Menu select [Results] tab > [Type : Analysis Result] > [Table] group > [Story Tables] > [Torsional Irregularity Check Table]
Input
From Record Activation Dialog, select the load cases/combinations for which Torsional Irregularity will be checked.
Refer to Usage of Table Tool and check the following data:
When Modules are not defined
Load Case : Load case/Combination
Story : Story ID
Level : Story Elevation
Height : Story Height
1. Average Value of Extreme Points
Story Drift: Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition
1.2*Story Drift: Story Drift multiplied by 1.2
Note 1
From Context Menu, select "Select Irregularity Ends" to select the ends.
Auto Calculation
Use auto-calculated "Average Value of Extreme Points" to evaluate the torsional irregularity at ends.
User Defined
Select User Defined and click the "Select Two End Nodes" Text Box. The view is then automatically converted to the Model View. Once the two end nodes are selected, 1.2 times the average story drift will be compared with the maximum story drift to evaluate torsional irregularity.
2. Maximum Value
Node: Node numbers corresponding to the maximum combined story drifts at each story level for the given loading condition
Story Drift: Maximum combined story drift at each story level for the given loading condition
3. Remark
"Story Drift of Maximum Value" divided by "1.2*Story Drift of Average Value of Extreme Points" If it exceeds 1.0, "Irregular" is printed. If it is less than 1.0, 'Regular' is printed.
When Modules are defined
The Module column is generated only when the Modules are defined. Torsional irregularity check results are generated as per the following Note.
Note
1. Irregularity check results for the top floors of each Module are not generated.
2. Story drifts used to evaluate torsional irregularity are calculated in the same manner as used in Results > Result Tables > Story > Story Drift.
Module : Module name is defined in Structure > Building > Story > Define Module button
Load Case : Load case/Combination
Story : Story ID
Level : Story Elevation
Height : Story Height
1. Average Value of Extreme Points
Story Drift: Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition
1.2*Story Drift: Story Drift multiplied by 1.2
Note 1
From Context Menu, select "Select Irregularity Ends" to select the ends.
Auto Calculation
Use auto-calculated "Average Value of Extreme Points" to evaluate the torsional irregularity at ends.
User Defined
Select User Defined and click the "Select Two End Nodes" Text Box. The view is then automatically converted to the Model View. Once the two end nodes are selected, 1.2 times the average story drift will be compared with the maximum story drift to evaluate torsional irregularity.
2. Maximum Value
Node: Node numbers corresponding to the maximum combined story drifts at each story level for the given loading condition
Story Drift: Maximum combined story drift at each story level for the given loading condition
3. Remark
"Story Drift of Maximum Value" divided by "1.2*Story Drift of Average Value of Extreme Points" If it exceeds 1.0, "Irregular" is printed. If it is less than 1.0, 'Regular' is printed.
When Modules are not defined
Load Case : Load case/Combination
Story : Story ID
Level : Story Elevation
Height : Story Height
1. Average Value of Extreme Points
1.4 Story Drift : Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.4
1.2*Story Drift : Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.2
Note
From Context Menu, select "Select Irregularity Ends" to select the ends.
Auto Calculation
Use auto-calculated "Average Value of Extreme Points" to evaluate the torsional irregularity at ends.
User Defined
Select User Defined and click the "Select Two End Nodes" Text Box. The view is then automatically converted to the Model View. Once the two end nodes are selected, 1.2 times the average story drift will be compared with the maximum story drift to evaluate torsional irregularity.
2. Maximum Value
Node : Node numbers corresponding to the maximum combined story drifts at corner (Extreme) points at each story level for the given loading condition
Story Drift : Maximum combined story drift at each story level at corner (Extreme) points for the given loading condition
3. Remark
"Story Drift of Maximum Value" is less than "1.2*Story Drift of Average Value of Extreme Points", "Regular" is printed.
"Story Drift of Maximum Value" exceeds "1.2*Story Drift of Average Value of Extreme Points" and less than "1.4*Story Drift of Average Value of Extreme Points" , "Irregular" is printed.
"Story Drift of Maximum Value" exceeds "1.4*Story Drift of Average Value of Extreme Points", "Extreme Irregular" is printed.
Note
Torsional Irregularity Check table is provided to check if a structure with rigid diaphragm, the maximum story drift, computed including accidental torsion evaluated with Ax = 1.0 and measured perpendicularly to an axis is more than 1.2 and less than or equal to 1.4 times the average of the story drifts at the two ends of the structure with respect to the same reference axis. Extreme Torsional Irregularity is displayed if the maximum story drift is more than 1.4 times the average of the story drifts at the two ends of the structure.
When Modules are defined
The Module column is generated only when the Modules are defined. Torsional irregularity check results are generated as per the following Note.
Note
1. Irregularity check results for the top floors of each Module are not generated.
2. Story drifts used to evaluate torsional irregularity are calculated in the same manner as used in Results > Result Tables > Story > Story Drift.
Module : Module name is defined in Structure > Building > Story > Define Module button
Load Case : Load case/Combination
Story : Story ID
Level : Story Elevation
Height : Story Height
1. Average Value of Extreme Points
1.4 Story Drift : Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.4
1.2*Story Drift : Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.2
Note
From Context Menu, select "Select Irregularity Ends" to select the ends.
Auto Calculation
Use auto-calculated "Average Value of Extreme Points" to evaluate the torsional irregularity at ends.
User Defined
Select User Defined and click the "Select Two End Nodes" Text Box. The view is then automatically converted to the Model View. Once the two end nodes are selected, 1.2 times the average story drift will be compared with the maximum story drift to evaluate torsional irregularity.
2. Maximum Value
Node : Node numbers corresponding to the maximum combined story drifts at corner (Extreme) points at each story level for the given loading condition
Story Drift : Maximum combined story drift at each story level at corner (Extreme) points for the given loading condition
3. Remark
"Story Drift of Maximum Value" is less than "1.2*Story Drift of Average Value of Extreme Points", "Regular" is printed.
"Story Drift of Maximum Value" exceeds "1.2*Story Drift of Average Value of Extreme Points" and less than "1.4*Story Drift of Average Value of Extreme Points" , "Irregular" is printed.
"Story Drift of Maximum Value" exceeds "1.4*Story Drift of Average Value of Extreme Points", "Extreme Irregular" is printed.
Note
Torsional Irregularity Check table is provided to check if a structure with rigid diaphragm, the maximum story drift, computed including accidental torsion evaluated with Ax = 1.0 and measured perpendicularly to an axis is more than 1.2 and less than or equal to 1.4 times the average of the story drifts at the two ends of the structure with respect to the same reference axis. Extreme Torsional Irregularity is displayed if the maximum story drift is more than 1.4 times the average of the story drifts at the two ends of the structure.
When Modules are not defined
Load Case: Load case/Combination
Story: Story ID
Level: Story Elevation
Height: Story Height
1. Average Value of Extreme Points
1.4 Story Drift: Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.4
1.2*Story Drift: Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.2
Note
From Context Menu, select "Select Irregularity Ends" to select the ends.
Auto Calculation
Use auto-calculated "Average Value of Extreme Points" to evaluate the torsional irregularity at ends.
User Defined
Select User Defined and click the "Select Two End Nodes" Text Box. The view is then automatically converted to the Model View. Once the two end nodes are selected, 1.2 times the average story drift will be compared with the maximum story drift to evaluate torsional irregularity.
2. Maximum Value
Node: Node numbers corresponding to the maximum combined story drifts at corner (Extreme) points at each story level for the given loading condition
Story Drift: Maximum combined story drift at each story level at corner (Extreme) points for the given loading condition
3. Remark
"Story Drift of Maximum Value" is less than "1.2*Story Drift of Average Value of Extreme Points", "Regular" is printed.
"Story Drift of Maximum Value" exceeds "1.2*Story Drift of Average Value of Extreme Points" and less than "1.4*
"Story Drift of Average Value of Extreme Points" , "Irregular-Building Config" is printed.
"Story Drift of Maximum Value" exceeds "1.4*Story Drift of Average Value of Extreme Points", "Irregular-Structure Config" is printed.
Note
Torsional Irregularity Check table is provided to check if a structure with rigid diaphragm, the maximum story drift, computed including accidental torsion evaluated with Ax = 1.0 and measured perpendicularly to an axis is more than 1.2 and less than or equal to 1.4 times the average of the story drifts at the two ends of the structure with respect to the same reference axis. Extreme Torsional Irregularity is displayed if the maximum story drift is more than 1.4 times the average of the story drifts at the two ends of the structure.
When Modules are defined
The Module column is generated only when the Modules are defined. Torsional irregularity check results are generated as per the following Note.
Note
1. Irregularity check results for the top floors of each Module are not generated.
2. Story drifts used to evaluate torsional irregularity are calculated in the same manner as used in Results > Result Tables > Story > Story Drift.
Module: Module name is defined in Structure > Building > Story > Define Module button
Load Case: Load case/Combination
Story: Story ID
Level: Story Elevation
Height: Story Height
1. Average Value of Extreme Points
1.4 Story Drift: Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.4
1.2*Story Drift: Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition multiplied by 1.2
Note
From Context Menu, select "Select Irregularity Ends" to select the ends.
Auto Calculation
Use auto-calculated "Average Value of Extreme Points" to evaluate the torsional irregularity at ends.
User Defined
Select User Defined and click the "Select Two End Nodes" Text Box. The view is then automatically converted to the Model View. Once the two end nodes are selected, 1.2 times the average story drift will be compared with the maximum story drift to evaluate torsional irregularity.
2. Maximum Value
Node: Node numbers corresponding to the maximum combined story drifts at corner (Extreme) points at each story level for the given loading condition
Story Drift: Maximum combined story drift at each story level at corner (Extreme) points for the given loading condition
3. Remark
"Story Drift of Maximum Value" is less than "1.2*Story Drift of Average Value of Extreme Points", "Regular" is printed.
"Story Drift of Maximum Value" exceeds "1.2*Story Drift of Average Value of Extreme Points" and less than "1.4*
"Story Drift of Average Value of Extreme Points" , "Irregular-Building Config" is printed.
"Story Drift of Maximum Value" exceeds "1.4*Story Drift of Average Value of Extreme Points", "Irregular-Structure Config" is printed.
Note
Torsional Irregularity Check table is provided to check if a structure with rigid diaphragm, the maximum story drift, computed including accidental torsion evaluated with Ax = 1.0 and measured perpendicularly to an axis is more than 1.2 and less than or equal to 1.4 times the average of the story drifts at the two ends of the structure with respect to the same reference axis. Extreme Torsional Irregularity is displayed if the maximum story drift is more than 1.4 times the average of the story drifts at the two ends of the structure.
When Modules are not defined
Load Case: Load case/Combination
Story: Story ID
Level: Story Elevation
Height: Story Height
1. Average Value of Extreme Points
Story Drift: Average of the combined story drifts of vertical members at corner (Extreme) points at a story for the given loading condition
1.15*Story Drift: Story Drift multiplied by 1.15
1.3*Story Drift: Story Drift multiplied by 1.3
1.4*Story Drift: Story Drift multiplied by 1.4
Note 1
From Context Menu, select "Select Irregularity Ends" to select the ends.
Auto Calculation
Use auto-calculated "Average Value of Extreme Points" to evaluate the torsional irregularity at ends.
User Defined
Select User Defined and click the "Select Two End Nodes" Text Box. The view is then automatically converted to the Model View. Once the two end nodes are selected, the specific times the average story drift will be compared with the maximum story drift to evaluate torsional irregularity.
2. Maximum Value
Node: Node numbers corresponding to the maximum combined story drifts at each story level for the given loading condition
Story Drift: Maximum combined story drift at each story level for the given loading condition
3. Remark
Regular : Max. Value =< 1.15*Average Value
Irregular : 1.15*Average Value < Max. Value =< 1.3*Average Value
Strong Irregular : 1.3*Average Value < Max. Value =< 1.4*Average Value
PBE (Peformance Based Evaluation) : 1.4*Average Value < Max. Value