Auto Base/Cap Plate (" Connection specifications " and more)

Also see :

user defined | auto standard | column | system | top


Design restrictions for auto base/cap plates :

  • In order for an auto base/cap plate to be designed, the column must frame to (under or over) a beam or a joist ( exception: an auto base/cap plate with ' Force ' does not require a framing condition). Auto base/cap plates can be applied to wide flange , S shape , welded plate wide flange , welded plate box , tube , or pipe columns. For columns that do not frame to a member, you can apply a user base/cap plate instead.
  • For a cap plate to be designed automatically, the top work point of the column may be at the same elevation as the beam as long as the work point of the beam is at least 1/16 inch past the work line of the column. If the beam does not go past the work line , the top work point of the column must be 1/16 inch below the half depth of the beam.
  • When ' Auto Standard ' is selected as the " Input connection type " on the Column Edit window, an auto/base cap plate is designed if the column's framing situation in the model matches an auto standard framing condition and ' Auto/base cap plate ' is selected at Home > Project Settings > Job > Auto Standard Connections as the " Input connection type " for that framing condition.
  • Auto base/cap plates have two bolt groups that are exterior to the face of each flange if the flanges of the column are perpendicular to the work line of the beam. This applies to wide flange , S shape and welded plate wide flange columns since those shapes have flanges. It does not apply to, for example, HSS columns or to a column whose " Column rotation " is set so that the flanges of the column are not perpendicular to the beam. Documentation for the " Column Plate " connection design locks provides more information. Also, be aware that if a vertical brace combines with the column and base or cap plate, the controls for the bolts exterior to the flange that are on the brace side of the column plate are controlled by the " Cap Plate " connection design locks on the Vertical Brace Edit window.
  • Connection design looks to relevant setup choices and the framing situation to design the auto base/cap plate. The " Load " on the column affects beam stiffener design.

user defined | auto standard | column | system | top


Advanced selection :

Expressions that can be used for Advanced Selection to select columns with auto base/cap plates:

# Selects columns with auto base plates.
m.Type == Column
and m.Ends[0].Designed.TypeDescription == AutomaticColumnPlate


# Selects columns with auto cap plates.
m.Type == Column
and m.Ends[1].Designed.TypeDescription == AutomaticColumnPlate


# Selects columns with top input connection set to auto base/cap.
m.Type == Column
and m.Ends[1].Input.TypeDescription == AutomaticColumnPlate


# Selects columns with auto standard auto base plates.
m.Type == Column
and m.Ends[0].Input.TypeDescription == AutoStandard
and m.Ends[0].Designed.TypeDescription == AutomaticColumnPlate


# Selects columns with auto base plates with stiffeners set to auto.
m.Type is Column
and m.Ends[0].Designed.TypeDescription is AutomaticColumnPlate
and m.Ends[0].Designed.UseTransverseBeamStiffener is Auto

user defined | auto standard | column | system | top


Setup of auto base/cap plates :

An auto base/cap plate must frame to a beam or to a joist unless it is a user defined or forced connection.

  Option Location     Effect
Edge distance
( )
Standard Cap Plate Settings Sets the hole edge distance from the width edge of the auto base/cap plate.
Standard Cap Plate Settings Standard Fabricator Connections Sets the minimum thickness of auto cap plates designed for column-to-beam framing situations.
Weld pattern on cap plate Weld Design Settings  Welds all around cap plates or only on the flanges of the column.
Weld pattern on base plate Weld Design Settings Welds all around base plates or only on the flanges of the column. 
Maximum weld size ... Weld Design Settings Sets the maximum weld size for auto base/cap plates.
Design transverse stiffeners for base/cap plate connection    Plate Design Settings Instructs connection design to create full-depth stiffeners on the beam As needed , Always , or Never .
Extended Flange Plate Settings ( )

Standard Fabricator Connections

Setup choices are applied when " Use extended stiffeners " is ' Yes '.

user defined | auto standard | column | system | top


------" Connection specifications " for column ' Auto base/cap plate ' connections ------

A column's " Connection specifications " change with the selected connection type. To get this set of conn specs to show up on the Column Edit window, select ' Auto base/cap plate ' as the " Input connection type ." For auto standard or user defined connections, conn specs are not on the Column Edit window, but can be found at Home > Project Settings > Job > Auto Standard Connections or User Defined Connections .

Weld pattern: Automatic or Two faces or All faces or All faces (with seal) or All around . The weld size that connection design uses for an auto base/cap plate's weld pattern is greater than or equal to the " Minimum for job " and less than or equal to the " Maximum for non-strength connections ," which are set at Home > Project Settings > Job > Weld Design Settings . " Seal weld size " at Home > Project Settings > Job > Weld Design Settings sets the weld size for the seal welds.

HSS Rectangular Columns Welded to Auto Bases Plates

Wide Flange Columns Welded to Auto Base Plates

' Automatic ' specifies that connection design apply the choice made for the weld pattern " On base plate " ( ) or weld pattern " On cap plate " at Home > Project Settings > Job > Weld Design Settings .

' Two faces ' instructs connection design to shop weld two opposite faces of the column to the auto base/cap plate. For a wide flange, the outside face of one flange is welded, and the inside faces (NS & FS) of the other flange are welded.

' All faces ' specifies that the faces except thickness edges and fillets and HSS corners be welded. For HSS rectangular sections, only the outside faces are welded. For wide flange, both inside and outside faces are welded.

' All faces (with seal) ' gives the same results that you would get for ' All faces ', except that thickness edges and fillets and HSS corners are seal welded. " Seal weld size " at Home > Project Settings > Job > Weld Design Settings sets the weld size for the seal weld. The tail text applied during Detail Members f for seal welds on HSS/TS columns is ' 4 SIDES WITH SEAL '. For columuns other than HSS/TS, the tail text is ' ALL FACES WITH SEAL '.

Seal weld symbol for HSS/TS column.

Seal weld symbol for wide flange column.

' All around ' shop welds around all faces of the column, including the thickness edges and fillets of a wide flange and the round corners of an HSS rectangular (tube).

Weld symbol for ' All around '.

For an HSS round (pipe) section, weld is all around the section (a complete circle), regardless of the choice made here.

HSS Round Columns Welded to Auto Base Plates
(all four choices produce the same result)

Connection design locks: Column Plate Welds ( )
Weld Design Settings: Maximum weld size for non-strength connections
Weld Design Settings: Seal weld size

Use transverse beam stiffener: Automatic or As needed or Always or Never. This " Connection specifications " option can apply when a column's auto base/cap plate connects to a beam flange.

' As needed ' or ' Always '
' Never '

' Automatic ' specifies that connection design apply the choice made to Home > Project Settings > Job > Design > Plate Design Settings > " Design transverse stiffener for base/cap plate connection ."

' As needed ' instructs connection design to create one pair of full-depth transverse beam stiffeners (one on the beam's near side, one far side), when the " Load is large enough that the supporting wide flange beam's web capacity is exceeded and stiffeners are required." Two pairs of stiffeners are created when the " Load " is sufficiently large. The two pairs of stiffeners align with the flanges of the column. A single pair of stiffeners is centered with respect to the column work line.

' Always ' instructs connection design to create at least one pair of full-depth transverse beam stiffeners (one on the beam's near side, one far side), regardless of the " Load ." Two pairs of stiffeners are created when the " Load " is sufficiently large. The two pairs of stiffeners align with the flanges of the column. A single pair of stiffeners is centered with respect to the column work line.

' Never ' instructs connection design to not create full-depth transverse beam stiffeners, even if they are required by connection design. A red banner will appear in " Information " that reads "Beam web design checks removed by user". This message will also appear in the column's design calculation.

Advanced Selection: UseTransverseBeamStiffener (also click here ).
Parametric module: UseTransverseBeamStiffener

Align stiffeners with: Automatic or Column or Beam . This " Connection specifications " option can apply when a column's auto base/cap plate bolts to the flange of a beam.

' Column '
' Beam '

' Automatic ' specifies that connection design apply the choice made to Home > Project Settings > Job > Design > Plate Design Settings > " Align transverse stiffeners for base/cap plate connection with ."

' Column ' instructs connection design to create transverse beam stiffeners that are parallel with the work line (stick form work line) of the column.

' Beam ' instructs connection design to create transverse beam stiffeners that are perpendicular to the work line of the beam. The stiffeners will be normal to the beam, regardless of the slope of the beam or column.

Use extended stiffeners: Automatic or Yes or No . This " Connection specifications " option can apply when a column's auto base plate frames to the top flange of a beam. It may also apply when an auto cap plate frames to the bottom flange of a beam.

VIDEO Flange extension plates with tapered stiffeners may be designed for a column with an auto or user base/cap plate framing to a beam with a flange that is narrower than the column plate. This video shows how to set up and generate these connection components.

A connection similar to this one may be created when ' Yes ' or ' Automatic ' is selected for " Use extended stiffeners ." The flange extension plates extend the effective flange width of the beam. NS and FS beam stiffeners are tapered to fit to the flange extension plates. The flange extensions are designed for erection purposes, not as structural supports.

' Automatic ' specifies that connection design look to Home > Project Settings > Fabricator > Standard Fabricator Connections > Extended Flange Plate Settings > " Plate overhang tolerance " to determine whether or not to design a connection. If the setup value is less than or equal to the actual base/cap plate overhang in the model, then a connection will be designed. If the setup value is greater than the overhang in the model, a connection will not be designed.

' Yes ' instructs connection design to attempt to design flange extension plates and stiffeners. If it is determined that such a connection should not be designed, for example, because of interference with another member, design locks are populated with null values (e.g. distances of ' 0 ') in leaves named " Bottom extension plate " or " Top extension plate " and " Stiffener Plate ."

' No ' instructs connection design to not design beam flange extension plates and beam stiffeners.

Note 1: Tapered stiffeners (as opposed to rectangular stiffeners) will be designed only when the option to " Clip beam stiffener " is on (checked) in Extended Flange Plate Settings .

Note 2: If stiffeners are not needed, setting " Use transverse beam stiffener " to ' No ' may cause them not to be designed.

Home > Project Settings > Fabricator > Standard Fabricator Connections > Extended Flange Plate Settings
Connection design locks: " Bottom extension plate " or " Top extension plate " and " Stiffener Plate "
Connection Guide: Beam flange extension plates with tapered stiffeners

Base/cap plate grade: Auto or user-entered .

' Auto ( checked )' specifies that connection design apply a setup choice ( Home > Project Settings > Fabricator > Standard Fabricator Connections > Plates > the " Column Cap/Base Pl " section > " Plate material grade ").

' Auto ( not checked )' lets you select a steel grade on the list box ( ). Choices on the list box come from Home > Project Settings > Job > Plate Grades .

user defined | auto standard | column | system | top


Connection design locks for auto base/cap plates :

Connection design locks for auto base/cap plates may appear, under a leaf with one of the below-listed names, on the Column Edit window or on a Connection Component window. The locks can also appear on the User Defined Connections window.

Connection Design Locks
(" Input connection type " = ' Auto base/cap plate ')
Leaf Name Situation   
Column Plate
(col to bm or joist)
These locks appear, for example, when ' Auto base/cap plate ' is selected as the " Input connection type " for a column to a beam or a joist. 
Column Plate
(column to nothing)
For a column that does not frame to a beam or joist. These locks may appear when you " Force " an auto base/cap plate. 
Stiffener Plate Beam stiffeners are only applicable for base/cap plates under or over beams. All fields have null values if beam stiffeners are not needed. 
Column Plate Welds
( )
You can turn on/off welds for each face of a column that can potentially be welded to the base/cap plate.
Top / Bottom Extension Plate (to a beam) Connection design locks in this leaf let you add or adjust flange extension plates to a beam.

user defined | auto standard | column | system | top