Other cross-section parameters

In addition to sectional characteristics, a cross-section in SCIA Engineer has some additional parameters such as name, type description, colour, etc.

The common parameters in SCIA Engineer (except the common sectional characteristics) are:

Name	A name of a cross-section. The name must be unique within one project. If an attempt to insert a name that already exists in the project, the typed name is not accepted and is automatically changed to a project-unique name.
Type	This parameter describes briefly the cross-section type so that the user can easily and quickly see what type the particular cross-section is.
Detailed (description)	Some cross-sections (e.g. welded ones) use this item to specify the cross-section type, shape and possibly dimensions in more detail.
Material	This item defines the material the cross-section is made of.
Draw colour
Colour	This item defines the colour that is used in SCIA Engineer to draw the cross-section in the cross-section manager.
Properties editable	If this option is not selected then it is not possible to edit individual calculated sectional characteristics. If the option is ON, some of the sectional characteristics may be manually edited in order to define the cross-section whose characteristics exactly correspond to particular conditions. The properties that can be edited are:  Ay, Az, It, Iw
Buckling y-y, z-z	These two parameters determine the buckling curve types used for buckling calculations.
Fabrication	This item specifies the way the cross-section is produced.
FEM analysis	If ON, the sectional characteristics are calculated using finite element method. See separate chapter Sectional characteristics calculated by FEM. If the FEM analysis is selected, the user can specify additional parameters: Mesh size This parameter specifies the size of the finite elements used for the calculation. IMPORTANT: Please, read chapter Sectional characteristics calculated by FEM for important notes relating to the mesh size. Min. point distance Specifies the minimum distance of two FEM nodes.   In order to see the calculated sectional characteristics, click button Update.
Curve dividing	This parameter is used ONLY in concrete checks for circular and curved edges of cross-sections . When a cross-section has a curved edge, it is substituted with a polyline (composed of straight lines). This parameter specifies how many straight line segments are used to represent the original curved edge.
Use property multipliers	Property multipliers are used to provide multiplication factors for selected properties. These multiplication factors can be used to either increase or decrease the selected property. For example, a multiplication factor 'k A' of 0,2 will lead to a sectional area of 20% instead of the full area. The modified property is used everywhere throughout SCIA Engineeri.e. for the self-weight, in the analysis, in Checks etc. The following coefficients are available: Multiplier Influenced Property k A Area k Ay Shear Area in principal y-direction k Az Shear Area in principal z-direction k It Torsional  constant k Iy Second moment of area about the principal y-axis k Iz Second moment of area about the principal z-axis Only the 'k A' multiplier has an influence on the self-weight. The other multiplication factors influence the stiffness matrix for the analysis but have no influence on the self-weight.
Edit named items	It is possible to name selected fibres of the cross-section and use these names as reference in display of results, etc.
Edit joints	It is possible to define joints and use them later.
Edit cuts	It is possible to define sections (cuts) across the cross-section and use them later.

Special parameters for Steel cross-sections when using code EC-EN

Initial shape subgroup

For thin-walled Steel cross-sections an Initial shape is defined by default. For a General cross-section the ‘Thin-walled representation’ has to be used to be able to define the Initial Shape.

More information can be found in the respective chapter of the Theoretical Background for EN 1993: "Initial Shape".

Initial shape

Within this dialog the Initial Shape can be reviewed.

Restrained by sheeting

When this option is selected the cross-section is assumed to be restrained by sheeting.

This prohibits bending about the principal axis and allows only bending about the local LCS axis.

Classification

This action runs the Classification dialog which performs the classification of the cross-section under different actions.

More information can be found in the respective chapter of the Theoretical Background for EN 1993: "Stress distribution"

Effective section

This action runs the effective section dialog which calculates the effective section properties under different actions.

More information can be found in the respective chapter of the Theoretical Background for EN 1993: "Effective Section properties"

Advanced procedure

This option allows the use of the Advanced procedure for calculation of effective section properties.

More information can be found in the respective chapter of the Theoretical Background for EN 1993:"Advanced Procedure for Effective Shape Calculation"

Initial shape subgroup in case of cold-formed cross-sections

In case of Steel cross-sections with fabrication cold-formed the Initial shape subgroup is extended with the following settings:

Free flange geometry

This setting is visible for selected section types and shows the geometry of the free flange for use in purlin design.

More information as well as a list of supported sections can be found in the respective chapter of the Theoretical Background for EN 1993:"Special considerations for Purlins"

Cold-formed subgroup

This subgroup shows specific settings for cold-formed sections.

Average yield strength

When this setting is activated the average yield strength as defined in EN 1993-1-3 is used.

More information can be found in the respective chapter of the Theoretical Background for EN 1993:"Material properties"

Steel core thickness

When this setting is activated the steel core thickness can be set as defined in EN 1993-1-3.

The thickness of the thin-walled elements are modified according to the inputted metallic coating and all section properties are recalculated.

More information can be found in the respective chapter of the Theoretical Background for EN 1993:"Material properties"

Special parameters for Steel cross-sections when using code SIA

Initial shape subgroup

For thin-walled Steel cross-sections an Initial shape is defined by default. For a General cross-section the ‘Thin-walled representation’ has to be used to be able to define the Initial Shape.

More information can be found in the respective chapter of the Theoretical Background for SIA 263: "Initial shape".

Initial shape

Within this dialog the Initial Shape can be reviewed.

Restrained by sheeting

When this option is selected the cross-section is assumed to be restrained by sheeting.

This prohibits bending about the principal axis and allows only bending about the local LCS axis.

Classification

This action runs the Classification dialog which performs the classification of the cross-section under different actions.

More information can be found in the respective chapter of the Theoretical Background for SIA 263: "Classification"

Effective section

This action runs the effective section dialog which calculates the effective section properties under different actions.

More information can be found in the respective chapter of the Theoretical Background for SIA 263: "Effective Section properties"

Special parameters for Aluminium cross-sections when using code EC-EN

Initial shape subgroup

For aluminium cross-sections an Initial shape can be defined. More information can be found in the Theoretical background manual and in code EN 1999-1-1:2007.

If the option is selected, the following additional parameters appear in the dialogue:

Edit initial shape

Within this dialog the Initial Shape can be modified. Specifically for Aluminium sections this allows the definition of welds on the different elements.

Restrained by sheeting

When this option is selected the cross-section is assumed to be restrained by sheeting.

This prohibits bending about the principal axis and allows only bending about the local LCS axis.

Classification and Effective section

This action runs the analysis of the reduced cross-section. Both the classification and effective shape calculation are part of this action.

Special parameters for Steel cross-sections when using code IBC

Initial shape subgroup

For thin-walled Steel cross-sections an Initial shape is defined by default. For a General cross-section the ‘Thin-walled representation’ has to be used to be able to define the Initial Shape.

If the option is selected, the following additional parameters appear in the dialogue:

Edit initial shape

Within this dialog the Initial Shape can be reviewed.

Restrained by sheeting

When this option is selected the cross-section is assumed to be restrained by sheeting.

This prohibits bending about the principal axis and allows only bending about the local LCS axis.

Classification and Effective section

This action runs the analysis of the reduced cross-section. Both the classification and effective shape calculation are part of this action.

 

In addition to the numerical data available for a cross-section, the program offers also a drawing of the cross-section with marked vertex numbers. The numbers are important mainly if the user includes a cross-section characteristics table into a document where some of the values correspond to individual vertices. Therefore, it is essential to know the convention of vertex numbering. The vertex numbers are given on a separate tab of the graphical window in the editing dialogue.