What is AISC-ASD 01?
This code is the AISC-ASD 2001 supplement #1 to the Specifications for Structural Steel Buildings.

Do we need to mesh the wall for an inverted chevron brace at top of shear wall?
We recommend that you mesh the shear wall at the inverted brace apex. If you don’t mesh the wall, you will need to turn on the auto line constraint option. (Under Assign>shell>auto line constraint).

Are stiffness values displayed for floor elements?
The stiffness property modifiers provided by the users are shown in the input data tables. The stiffness matrix is created internally and is not viewable by the user.

What changes are being made in ETABS for Non-Linear time history analysis in the future?
In ETABS version 9, direct integration time history analysis will be available.
Currently, this option is only available in SAP2000.

Are all hinge properties based upon FEMA 356?
Currently, in ETABS version 8, all hinge properties are based on FEMA 273. In ETABS version 9, all hinge properties will be based upon FEMA 356.

How does the distribution of mass for wall/spandrels work in ETABS?
When running an analysis, the mass is lumped at the nodes of the internal elements. If the ‘Lump lateral mass at story levels’ option is checked (under Define>Mass Source), the mass at the internal points is assigned at the story levels.

When I assign a different cardinal point on a beam, the height of the column is not changing. Why is that?
In ETABS version 9, the clear length of the column will change according to the cardinal point specification. Currently, ETABS 8 does not perform this function.

Does ETABS perform large displacement analysis like SAP2000?
In ETABS version 9, when direct integration time history analysis is introduced, large displacement analysis will be available. Currently, this is only available for static Non Linear problems.

Do I need any preliminary design when working on a steel building?
No, you do not need any preliminary design. ETABS gives you the option to have the program select the steel sections for you using the Auto Select option. Auto select section lists are simply lists of previously defined steel sections. These are useful for Steel Frame Design and Composite Beam Design where ETABS can pick the optimal section for a steel frame element from an Auto Select Section List. There must be at least two steel frame sections defined before you are allowed to define an auto select section list. This steel section (Wide Flanges, Angles, Tubes, etc.) selection is based on stress or deflection. You can set a displacement target for selected joints. ETABS will then select a section for beams and columns that does not exceed the specified displacement.

What is the importance of the construction sequence loading option in ETABS?
To analyze incremental construction, the structure is modeled as a series of stages. Each stage is represented by a group of objects (points, lines, and areas) called an active group. You may change the active groups (stages) within a static nonlinear case and/or between consecutive static nonlinear cases. In the most common case of construction sequencing, each subsequent active group will include the previous active group plus some additional objects. However it is also possible to remove objects from one stage to the next.
Each change in stage is analyzed separately. If multiple stages are considered within a single static nonlinear case, multiple analyses are performed within that case and the results of all of these analyses are available as a single case. When changing stages within a single case, all added elements are subject to the same load pattern.
When analyzing the change in the structure from one stage to the next, the program looks for objects that are present in one active group but not the other. For further information, see Help menu in ETABS.

What are section cuts?
Section cuts allow you to get resultant forces acting at section cuts through your structure. You can define section cuts before or after you run an analysis. Typically you should not define section cuts, and more importantly the groups used in the section cut definition, until you have completed all manual meshing of your model (if any). If you define these groups before manual meshing then some of the point objects that should be in the group may not yet be created. It is safest to wait until after you have run the analysis to define the section cuts.

How does Foundation Design work in ETABS?
In ETABS, you can model a slab element including strip footings, mat foundations, columns, etc. Next, you can export this file and save it as an .F2k file. You have the option to export floor loads plus column and wall distortions. Import the same .F2k file into SAFE. The loads and moments applied to the foundation in ETABS will be exported to SAFE. Make any further changes to the model in SAFE and run the analysis. After the analysis is completed, run the design portion of the program. Then use CSIDetailer in SAFE, which is a new completely integrated software package that automatically produces drawings of reinforcing details for slabs that have been analyzed and designed using SAFE.

Are there any AutoCAD links in ETABS?
In ETABS, you have the option of exporting a specific story of a model or the entire structure to an AutoCAD (.DXF) file. In doing so, you can assign areas, beams, columns, etc. all to different layers in AutoCAD. Under the file menu, select Export>save as 3D DXF or Save story plan as .DXF to execute this option.

How can I account for cracking in concrete shear walls in my model?
To account for cracking in concrete shear walls, you must assign shell stiffness modifiers. This is located under Assign>Shell> Shell element modifiers. The f11, f22 and f12 modifiers are essentially equivalent to modification factors on the thickness of the shell element. The m11, m22 and m12 modifiers are essentially equivalent to modification factors on the thickness3 of the shell element.

How does ETABS account for deformations in the panel zone?
In ETABS, you can explicitly assign panel zones to specific joints in your model. When panel zones are assigned, ETABS puts a link between the column and the beam. The user has the option to modify the link properties under Assign>Joint/Point>Panel Zones.

Does this behavior extend beyond the elastic limits?
Yes, the user has the option of defining the link properties. Under Define>Link Properties, you can define a nonlinear link element.

Are stiffness values displayed for floor elements?
The stiffness matrix is created internally and is not viewable to the user. The stiffness property modifiers provided by the user are shown in the input data tables.

What changes are being made in ETABS for Non-Linear time history analysis in the future?
In ETABS version 9, direct integration time history analysis will be available.
Currently, this option is only available in SAP2000.

Are all hinge properties based upon FEMA 356?
Currently, in ETABS version 8, all hinge properties are based on FEMA 273. In ETABS version 9, all hinge properties will be based upon FEMA 356.

How does the distribution of mass for wall/spandrels work in ETABS?
When running an analysis, the mass is lumped at the nodes of the internal elements. If the ‘Lump lateral mass at story levels’ option is checked (under Define>Mass Source), the mass at the internal points is assigned at the story levels.

When I assign a different cardinal point on a beam, the height of the column is not changing. Why is that?
In ETABS version 9, the clear length of the column will change according to the cardinal point specification. Currently, ETABS 8 does not perform this function.

Does ETABS perform large displacement analysis like SAP2000?
In ETABS version 9, when direct integration time history analysis is introduced, large displacement analysis will be available. Currently, this is only available for static Non Linear problems.