The Section object stores the data describing a single section within the sections library.  Most of the properties in this object provide access to all of the geometric properties of the section that are used for analysis and design.  Other properties store the sections name, its shape and details of it symmetry.  The properties of the Section object are listed in the four tables shown below.  The first two tables lists all the properties and method of the Section object that do not directly access the section properties of the section.  The next table lists properties of the Section object that reference the dimensions of the section while the final table lists the properties for accessing the derived section properties of the section such as it’s area and moments of area.

Note that the naming convention for the elastic and plastic section modulii do not follow the naming convention generally adopted in the United States.  In the Multiframe automation interface, the elastic plastic modulus is denoted using a Z while the plastic section modulus is denoted using an S.

A new section may be added to a group using the AddSection method of the Sections collection.  This method takes up to ten parameters that specify the shape, name and dimensions of the sections.  The last four parameters are optional and specify additional dimensions of the section that are only required by the more complicated section shapes.  An example of adding a new I section to the Frame group of the sections library is demonstrated in the following code.

Dim mySection as Multiframe.Section
 Dim Name as String

’Add new I section, 600 deep and 300 wide
With mfApp.SectionsLibrary.Groups(“Frame”).Sections
  Set mySection =.AddSection(mfSectionI,”600x300I”,600,300,10,10)
End With

A number of sections may also be added to a group within the section library using a single call to the AddSections method.  This method takes the same parameters as the AddSection method except that the name and dimensions parameters may be arrays of values with each entry in the array corresponding to a new section to be created.  If only a single value is specified for one of the parameters, this value will be adopted for all of the sections to be created.  The AddSections method returns a SectionList object containing each of the new sections that have been added to the sections library.

Dim mySectList as Multiframe.SectionList
Dim Names(1 to 5) as string
Dim Widths(1 to 5) as double
Dim I as long

’ Generate names and width for sections
For I=1 to 5
  Widths(I) = (I+1)*100.0
  Names = “900x” & Str(Widths(I)) & ”I”
Next

’Add new I sections to Frame group
With mfApp.SectionsLibrary.Groups(“Frame”).Sections
  Set mySectList =.AddSections(mfSectionI, Names,900, Widths,8,12)
End With

The name of the section is referenced via the Name property of the Section object.  This property is a string that can be up to 31 characters long.  The name of the section can also be accessed via the hidden Label property of the SectionGroup object

The Shape property is an enumerated value of type mfSectionShape that identifies the shape of the section.  This enumerated type has values corresponding to each of the standard section shapes supported within Multiframe.

The SymmetricXX and SymmetricYY are Boolean properties of the Section object and return a value of true if the section is symmetric about the x or y axes respectively.  These properties are derived from the shape of the section but if the shape is non-standard, the symmetry of the section will be determined from its section properties.

The SectionGroup, SectionsLibrary and Application objects return the parent objects containing the Section object.

The section properties of the section can also be accessed via the GetProperty method of the Section object.  This method accepts a single parameter of type mfSectionProp that identifies the property of the section to be returned.  The values of the properties may also be set using the SetProperty method.  This method takes two parameters; the first identifies that section property and the second the new value of the section property.

The Compute method of the Section object calculates the section properties of the section from its shape and dimensions.  This method will generally be called after adding a new section to the sections library.  The example shown above for adding sections to the Frame group would generally be extended to compute the properties of the section as listed below.

Dim section as Multiframe.Section
Dim mySectList as Multiframe.SectionList
Dim Names(1 to 5) as string
Dim Widths(1 to 5) as double
Dim I as long

’Generate names and width for sections
For I=1 to 5
  Widths(I) = (I+1)*100.0
  Names = “900x” & Str(Widths(I)) & ”I”
Next

’Add new I sections to Frame group
With mfApp.SectionsLibrary.Groups(“Frame”).Sections
  Set mySectList =.AddSections(mfSectionI, Names,900, Widths,8,12)
End With

’Compute properties of new sections
With each section in mySectList
  .Compute()
End With

Locked Groups

A sections group may be set as locked in which case the properties of the group and the sections it contains cannot be modified.  This prevents the user from inadvertently modifying data within groups containing standard sections.